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-rw-r--r--sha1_file.c2466
1 files changed, 2466 insertions, 0 deletions
diff --git a/sha1_file.c b/sha1_file.c
new file mode 100644
index 0000000000..aca741b79c
--- /dev/null
+++ b/sha1_file.c
@@ -0,0 +1,2466 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ *
+ * This handles basic git sha1 object files - packing, unpacking,
+ * creation etc.
+ */
+#include "cache.h"
+#include "delta.h"
+#include "pack.h"
+#include "blob.h"
+#include "commit.h"
+#include "tag.h"
+#include "tree.h"
+#include "refs.h"
+
+#ifndef O_NOATIME
+#if defined(__linux__) && (defined(__i386__) || defined(__PPC__))
+#define O_NOATIME 01000000
+#else
+#define O_NOATIME 0
+#endif
+#endif
+
+#ifdef NO_C99_FORMAT
+#define SZ_FMT "lu"
+#else
+#define SZ_FMT "zu"
+#endif
+
+const unsigned char null_sha1[20];
+
+static unsigned int sha1_file_open_flag = O_NOATIME;
+
+const signed char hexval_table[256] = {
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 00-07 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 08-0f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 10-17 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 18-1f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 20-27 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 28-2f */
+ 0, 1, 2, 3, 4, 5, 6, 7, /* 30-37 */
+ 8, 9, -1, -1, -1, -1, -1, -1, /* 38-3f */
+ -1, 10, 11, 12, 13, 14, 15, -1, /* 40-47 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 48-4f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 50-57 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 58-5f */
+ -1, 10, 11, 12, 13, 14, 15, -1, /* 60-67 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 68-67 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 70-77 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 78-7f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 80-87 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 88-8f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 90-97 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* 98-9f */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* a0-a7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* a8-af */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* b0-b7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* b8-bf */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* c0-c7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* c8-cf */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* d0-d7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* d8-df */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* e0-e7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* e8-ef */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* f0-f7 */
+ -1, -1, -1, -1, -1, -1, -1, -1, /* f8-ff */
+};
+
+int get_sha1_hex(const char *hex, unsigned char *sha1)
+{
+ int i;
+ for (i = 0; i < 20; i++) {
+ unsigned int val = (hexval(hex[0]) << 4) | hexval(hex[1]);
+ if (val & ~0xff)
+ return -1;
+ *sha1++ = val;
+ hex += 2;
+ }
+ return 0;
+}
+
+int safe_create_leading_directories(char *path)
+{
+ char *pos = path;
+ struct stat st;
+
+ if (*pos == '/')
+ pos++;
+
+ while (pos) {
+ pos = strchr(pos, '/');
+ if (!pos)
+ break;
+ *pos = 0;
+ if (!stat(path, &st)) {
+ /* path exists */
+ if (!S_ISDIR(st.st_mode)) {
+ *pos = '/';
+ return -3;
+ }
+ }
+ else if (mkdir(path, 0777)) {
+ *pos = '/';
+ return -1;
+ }
+ else if (adjust_shared_perm(path)) {
+ *pos = '/';
+ return -2;
+ }
+ *pos++ = '/';
+ }
+ return 0;
+}
+
+char * sha1_to_hex(const unsigned char *sha1)
+{
+ static int bufno;
+ static char hexbuffer[4][50];
+ static const char hex[] = "0123456789abcdef";
+ char *buffer = hexbuffer[3 & ++bufno], *buf = buffer;
+ int i;
+
+ for (i = 0; i < 20; i++) {
+ unsigned int val = *sha1++;
+ *buf++ = hex[val >> 4];
+ *buf++ = hex[val & 0xf];
+ }
+ *buf = '\0';
+
+ return buffer;
+}
+
+static void fill_sha1_path(char *pathbuf, const unsigned char *sha1)
+{
+ int i;
+ for (i = 0; i < 20; i++) {
+ static char hex[] = "0123456789abcdef";
+ unsigned int val = sha1[i];
+ char *pos = pathbuf + i*2 + (i > 0);
+ *pos++ = hex[val >> 4];
+ *pos = hex[val & 0xf];
+ }
+}
+
+/*
+ * NOTE! This returns a statically allocated buffer, so you have to be
+ * careful about using it. Do a "xstrdup()" if you need to save the
+ * filename.
+ *
+ * Also note that this returns the location for creating. Reading
+ * SHA1 file can happen from any alternate directory listed in the
+ * DB_ENVIRONMENT environment variable if it is not found in
+ * the primary object database.
+ */
+char *sha1_file_name(const unsigned char *sha1)
+{
+ static char *name, *base;
+
+ if (!base) {
+ const char *sha1_file_directory = get_object_directory();
+ int len = strlen(sha1_file_directory);
+ base = xmalloc(len + 60);
+ memcpy(base, sha1_file_directory, len);
+ memset(base+len, 0, 60);
+ base[len] = '/';
+ base[len+3] = '/';
+ name = base + len + 1;
+ }
+ fill_sha1_path(name, sha1);
+ return base;
+}
+
+char *sha1_pack_name(const unsigned char *sha1)
+{
+ static const char hex[] = "0123456789abcdef";
+ static char *name, *base, *buf;
+ int i;
+
+ if (!base) {
+ const char *sha1_file_directory = get_object_directory();
+ int len = strlen(sha1_file_directory);
+ base = xmalloc(len + 60);
+ sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.pack", sha1_file_directory);
+ name = base + len + 11;
+ }
+
+ buf = name;
+
+ for (i = 0; i < 20; i++) {
+ unsigned int val = *sha1++;
+ *buf++ = hex[val >> 4];
+ *buf++ = hex[val & 0xf];
+ }
+
+ return base;
+}
+
+char *sha1_pack_index_name(const unsigned char *sha1)
+{
+ static const char hex[] = "0123456789abcdef";
+ static char *name, *base, *buf;
+ int i;
+
+ if (!base) {
+ const char *sha1_file_directory = get_object_directory();
+ int len = strlen(sha1_file_directory);
+ base = xmalloc(len + 60);
+ sprintf(base, "%s/pack/pack-1234567890123456789012345678901234567890.idx", sha1_file_directory);
+ name = base + len + 11;
+ }
+
+ buf = name;
+
+ for (i = 0; i < 20; i++) {
+ unsigned int val = *sha1++;
+ *buf++ = hex[val >> 4];
+ *buf++ = hex[val & 0xf];
+ }
+
+ return base;
+}
+
+struct alternate_object_database *alt_odb_list;
+static struct alternate_object_database **alt_odb_tail;
+
+static void read_info_alternates(const char * alternates, int depth);
+
+/*
+ * Prepare alternate object database registry.
+ *
+ * The variable alt_odb_list points at the list of struct
+ * alternate_object_database. The elements on this list come from
+ * non-empty elements from colon separated ALTERNATE_DB_ENVIRONMENT
+ * environment variable, and $GIT_OBJECT_DIRECTORY/info/alternates,
+ * whose contents is similar to that environment variable but can be
+ * LF separated. Its base points at a statically allocated buffer that
+ * contains "/the/directory/corresponding/to/.git/objects/...", while
+ * its name points just after the slash at the end of ".git/objects/"
+ * in the example above, and has enough space to hold 40-byte hex
+ * SHA1, an extra slash for the first level indirection, and the
+ * terminating NUL.
+ */
+static int link_alt_odb_entry(const char * entry, int len, const char * relative_base, int depth)
+{
+ struct stat st;
+ const char *objdir = get_object_directory();
+ struct alternate_object_database *ent;
+ struct alternate_object_database *alt;
+ /* 43 = 40-byte + 2 '/' + terminating NUL */
+ int pfxlen = len;
+ int entlen = pfxlen + 43;
+ int base_len = -1;
+
+ if (*entry != '/' && relative_base) {
+ /* Relative alt-odb */
+ if (base_len < 0)
+ base_len = strlen(relative_base) + 1;
+ entlen += base_len;
+ pfxlen += base_len;
+ }
+ ent = xmalloc(sizeof(*ent) + entlen);
+
+ if (*entry != '/' && relative_base) {
+ memcpy(ent->base, relative_base, base_len - 1);
+ ent->base[base_len - 1] = '/';
+ memcpy(ent->base + base_len, entry, len);
+ }
+ else
+ memcpy(ent->base, entry, pfxlen);
+
+ ent->name = ent->base + pfxlen + 1;
+ ent->base[pfxlen + 3] = '/';
+ ent->base[pfxlen] = ent->base[entlen-1] = 0;
+
+ /* Detect cases where alternate disappeared */
+ if (stat(ent->base, &st) || !S_ISDIR(st.st_mode)) {
+ error("object directory %s does not exist; "
+ "check .git/objects/info/alternates.",
+ ent->base);
+ free(ent);
+ return -1;
+ }
+
+ /* Prevent the common mistake of listing the same
+ * thing twice, or object directory itself.
+ */
+ for (alt = alt_odb_list; alt; alt = alt->next) {
+ if (!memcmp(ent->base, alt->base, pfxlen)) {
+ free(ent);
+ return -1;
+ }
+ }
+ if (!memcmp(ent->base, objdir, pfxlen)) {
+ free(ent);
+ return -1;
+ }
+
+ /* add the alternate entry */
+ *alt_odb_tail = ent;
+ alt_odb_tail = &(ent->next);
+ ent->next = NULL;
+
+ /* recursively add alternates */
+ read_info_alternates(ent->base, depth + 1);
+
+ ent->base[pfxlen] = '/';
+
+ return 0;
+}
+
+static void link_alt_odb_entries(const char *alt, const char *ep, int sep,
+ const char *relative_base, int depth)
+{
+ const char *cp, *last;
+
+ if (depth > 5) {
+ error("%s: ignoring alternate object stores, nesting too deep.",
+ relative_base);
+ return;
+ }
+
+ last = alt;
+ while (last < ep) {
+ cp = last;
+ if (cp < ep && *cp == '#') {
+ while (cp < ep && *cp != sep)
+ cp++;
+ last = cp + 1;
+ continue;
+ }
+ while (cp < ep && *cp != sep)
+ cp++;
+ if (last != cp) {
+ if ((*last != '/') && depth) {
+ error("%s: ignoring relative alternate object store %s",
+ relative_base, last);
+ } else {
+ link_alt_odb_entry(last, cp - last,
+ relative_base, depth);
+ }
+ }
+ while (cp < ep && *cp == sep)
+ cp++;
+ last = cp;
+ }
+}
+
+static void read_info_alternates(const char * relative_base, int depth)
+{
+ char *map;
+ size_t mapsz;
+ struct stat st;
+ const char alt_file_name[] = "info/alternates";
+ /* Given that relative_base is no longer than PATH_MAX,
+ ensure that "path" has enough space to append "/", the
+ file name, "info/alternates", and a trailing NUL. */
+ char path[PATH_MAX + 1 + sizeof alt_file_name];
+ int fd;
+
+ sprintf(path, "%s/%s", relative_base, alt_file_name);
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ return;
+ if (fstat(fd, &st) || (st.st_size == 0)) {
+ close(fd);
+ return;
+ }
+ mapsz = xsize_t(st.st_size);
+ map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+
+ link_alt_odb_entries(map, map + mapsz, '\n', relative_base, depth);
+
+ munmap(map, mapsz);
+}
+
+void prepare_alt_odb(void)
+{
+ const char *alt;
+
+ if (alt_odb_tail)
+ return;
+
+ alt = getenv(ALTERNATE_DB_ENVIRONMENT);
+ if (!alt) alt = "";
+
+ alt_odb_tail = &alt_odb_list;
+ link_alt_odb_entries(alt, alt + strlen(alt), ':', NULL, 0);
+
+ read_info_alternates(get_object_directory(), 0);
+}
+
+static char *find_sha1_file(const unsigned char *sha1, struct stat *st)
+{
+ char *name = sha1_file_name(sha1);
+ struct alternate_object_database *alt;
+
+ if (!stat(name, st))
+ return name;
+ prepare_alt_odb();
+ for (alt = alt_odb_list; alt; alt = alt->next) {
+ name = alt->name;
+ fill_sha1_path(name, sha1);
+ if (!stat(alt->base, st))
+ return alt->base;
+ }
+ return NULL;
+}
+
+static unsigned int pack_used_ctr;
+static unsigned int pack_mmap_calls;
+static unsigned int peak_pack_open_windows;
+static unsigned int pack_open_windows;
+static size_t peak_pack_mapped;
+static size_t pack_mapped;
+struct packed_git *packed_git;
+
+void pack_report(void)
+{
+ fprintf(stderr,
+ "pack_report: getpagesize() = %10" SZ_FMT "\n"
+ "pack_report: core.packedGitWindowSize = %10" SZ_FMT "\n"
+ "pack_report: core.packedGitLimit = %10" SZ_FMT "\n",
+ (size_t) getpagesize(),
+ packed_git_window_size,
+ packed_git_limit);
+ fprintf(stderr,
+ "pack_report: pack_used_ctr = %10u\n"
+ "pack_report: pack_mmap_calls = %10u\n"
+ "pack_report: pack_open_windows = %10u / %10u\n"
+ "pack_report: pack_mapped = "
+ "%10" SZ_FMT " / %10" SZ_FMT "\n",
+ pack_used_ctr,
+ pack_mmap_calls,
+ pack_open_windows, peak_pack_open_windows,
+ pack_mapped, peak_pack_mapped);
+}
+
+static int check_packed_git_idx(const char *path, struct packed_git *p)
+{
+ void *idx_map;
+ struct pack_idx_header *hdr;
+ size_t idx_size;
+ uint32_t version, nr, i, *index;
+ int fd = open(path, O_RDONLY);
+ struct stat st;
+
+ if (fd < 0)
+ return -1;
+ if (fstat(fd, &st)) {
+ close(fd);
+ return -1;
+ }
+ idx_size = xsize_t(st.st_size);
+ if (idx_size < 4 * 256 + 20 + 20) {
+ close(fd);
+ return error("index file %s is too small", path);
+ }
+ idx_map = xmmap(NULL, idx_size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+
+ hdr = idx_map;
+ if (hdr->idx_signature == htonl(PACK_IDX_SIGNATURE)) {
+ version = ntohl(hdr->idx_version);
+ if (version < 2 || version > 2) {
+ munmap(idx_map, idx_size);
+ return error("index file %s is version %d"
+ " and is not supported by this binary"
+ " (try upgrading GIT to a newer version)",
+ path, version);
+ }
+ } else
+ version = 1;
+
+ nr = 0;
+ index = idx_map;
+ if (version > 1)
+ index += 2; /* skip index header */
+ for (i = 0; i < 256; i++) {
+ uint32_t n = ntohl(index[i]);
+ if (n < nr) {
+ munmap(idx_map, idx_size);
+ return error("non-monotonic index %s", path);
+ }
+ nr = n;
+ }
+
+ if (version == 1) {
+ /*
+ * Total size:
+ * - 256 index entries 4 bytes each
+ * - 24-byte entries * nr (20-byte sha1 + 4-byte offset)
+ * - 20-byte SHA1 of the packfile
+ * - 20-byte SHA1 file checksum
+ */
+ if (idx_size != 4*256 + nr * 24 + 20 + 20) {
+ munmap(idx_map, idx_size);
+ return error("wrong index file size in %s", path);
+ }
+ } else if (version == 2) {
+ /*
+ * Minimum size:
+ * - 8 bytes of header
+ * - 256 index entries 4 bytes each
+ * - 20-byte sha1 entry * nr
+ * - 4-byte crc entry * nr
+ * - 4-byte offset entry * nr
+ * - 20-byte SHA1 of the packfile
+ * - 20-byte SHA1 file checksum
+ * And after the 4-byte offset table might be a
+ * variable sized table containing 8-byte entries
+ * for offsets larger than 2^31.
+ */
+ unsigned long min_size = 8 + 4*256 + nr*(20 + 4 + 4) + 20 + 20;
+ unsigned long max_size = min_size;
+ if (nr)
+ max_size += (nr - 1)*8;
+ if (idx_size < min_size || idx_size > max_size) {
+ munmap(idx_map, idx_size);
+ return error("wrong index file size in %s", path);
+ }
+ if (idx_size != min_size) {
+ /* make sure we can deal with large pack offsets */
+ off_t x = 0x7fffffffUL, y = 0xffffffffUL;
+ if (x > (x + 1) || y > (y + 1)) {
+ munmap(idx_map, idx_size);
+ return error("pack too large for current definition of off_t in %s", path);
+ }
+ }
+ }
+
+ p->index_version = version;
+ p->index_data = idx_map;
+ p->index_size = idx_size;
+ p->num_objects = nr;
+ return 0;
+}
+
+int open_pack_index(struct packed_git *p)
+{
+ char *idx_name;
+ int ret;
+
+ if (p->index_data)
+ return 0;
+
+ idx_name = xstrdup(p->pack_name);
+ strcpy(idx_name + strlen(idx_name) - strlen(".pack"), ".idx");
+ ret = check_packed_git_idx(idx_name, p);
+ free(idx_name);
+ return ret;
+}
+
+static void scan_windows(struct packed_git *p,
+ struct packed_git **lru_p,
+ struct pack_window **lru_w,
+ struct pack_window **lru_l)
+{
+ struct pack_window *w, *w_l;
+
+ for (w_l = NULL, w = p->windows; w; w = w->next) {
+ if (!w->inuse_cnt) {
+ if (!*lru_w || w->last_used < (*lru_w)->last_used) {
+ *lru_p = p;
+ *lru_w = w;
+ *lru_l = w_l;
+ }
+ }
+ w_l = w;
+ }
+}
+
+static int unuse_one_window(struct packed_git *current, int keep_fd)
+{
+ struct packed_git *p, *lru_p = NULL;
+ struct pack_window *lru_w = NULL, *lru_l = NULL;
+
+ if (current)
+ scan_windows(current, &lru_p, &lru_w, &lru_l);
+ for (p = packed_git; p; p = p->next)
+ scan_windows(p, &lru_p, &lru_w, &lru_l);
+ if (lru_p) {
+ munmap(lru_w->base, lru_w->len);
+ pack_mapped -= lru_w->len;
+ if (lru_l)
+ lru_l->next = lru_w->next;
+ else {
+ lru_p->windows = lru_w->next;
+ if (!lru_p->windows && lru_p->pack_fd != keep_fd) {
+ close(lru_p->pack_fd);
+ lru_p->pack_fd = -1;
+ }
+ }
+ free(lru_w);
+ pack_open_windows--;
+ return 1;
+ }
+ return 0;
+}
+
+void release_pack_memory(size_t need, int fd)
+{
+ size_t cur = pack_mapped;
+ while (need >= (cur - pack_mapped) && unuse_one_window(NULL, fd))
+ ; /* nothing */
+}
+
+void unuse_pack(struct pack_window **w_cursor)
+{
+ struct pack_window *w = *w_cursor;
+ if (w) {
+ w->inuse_cnt--;
+ *w_cursor = NULL;
+ }
+}
+
+/*
+ * Do not call this directly as this leaks p->pack_fd on error return;
+ * call open_packed_git() instead.
+ */
+static int open_packed_git_1(struct packed_git *p)
+{
+ struct stat st;
+ struct pack_header hdr;
+ unsigned char sha1[20];
+ unsigned char *idx_sha1;
+ long fd_flag;
+
+ if (!p->index_data && open_pack_index(p))
+ return error("packfile %s index unavailable", p->pack_name);
+
+ p->pack_fd = open(p->pack_name, O_RDONLY);
+ if (p->pack_fd < 0 || fstat(p->pack_fd, &st))
+ return -1;
+
+ /* If we created the struct before we had the pack we lack size. */
+ if (!p->pack_size) {
+ if (!S_ISREG(st.st_mode))
+ return error("packfile %s not a regular file", p->pack_name);
+ p->pack_size = st.st_size;
+ } else if (p->pack_size != st.st_size)
+ return error("packfile %s size changed", p->pack_name);
+
+ /* We leave these file descriptors open with sliding mmap;
+ * there is no point keeping them open across exec(), though.
+ */
+ fd_flag = fcntl(p->pack_fd, F_GETFD, 0);
+ if (fd_flag < 0)
+ return error("cannot determine file descriptor flags");
+ fd_flag |= FD_CLOEXEC;
+ if (fcntl(p->pack_fd, F_SETFD, fd_flag) == -1)
+ return error("cannot set FD_CLOEXEC");
+
+ /* Verify we recognize this pack file format. */
+ if (read_in_full(p->pack_fd, &hdr, sizeof(hdr)) != sizeof(hdr))
+ return error("file %s is far too short to be a packfile", p->pack_name);
+ if (hdr.hdr_signature != htonl(PACK_SIGNATURE))
+ return error("file %s is not a GIT packfile", p->pack_name);
+ if (!pack_version_ok(hdr.hdr_version))
+ return error("packfile %s is version %u and not supported"
+ " (try upgrading GIT to a newer version)",
+ p->pack_name, ntohl(hdr.hdr_version));
+
+ /* Verify the pack matches its index. */
+ if (p->num_objects != ntohl(hdr.hdr_entries))
+ return error("packfile %s claims to have %u objects"
+ " while index indicates %u objects",
+ p->pack_name, ntohl(hdr.hdr_entries),
+ p->num_objects);
+ if (lseek(p->pack_fd, p->pack_size - sizeof(sha1), SEEK_SET) == -1)
+ return error("end of packfile %s is unavailable", p->pack_name);
+ if (read_in_full(p->pack_fd, sha1, sizeof(sha1)) != sizeof(sha1))
+ return error("packfile %s signature is unavailable", p->pack_name);
+ idx_sha1 = ((unsigned char *)p->index_data) + p->index_size - 40;
+ if (hashcmp(sha1, idx_sha1))
+ return error("packfile %s does not match index", p->pack_name);
+ return 0;
+}
+
+static int open_packed_git(struct packed_git *p)
+{
+ if (!open_packed_git_1(p))
+ return 0;
+ if (p->pack_fd != -1) {
+ close(p->pack_fd);
+ p->pack_fd = -1;
+ }
+ return -1;
+}
+
+static int in_window(struct pack_window *win, off_t offset)
+{
+ /* We must promise at least 20 bytes (one hash) after the
+ * offset is available from this window, otherwise the offset
+ * is not actually in this window and a different window (which
+ * has that one hash excess) must be used. This is to support
+ * the object header and delta base parsing routines below.
+ */
+ off_t win_off = win->offset;
+ return win_off <= offset
+ && (offset + 20) <= (win_off + win->len);
+}
+
+unsigned char* use_pack(struct packed_git *p,
+ struct pack_window **w_cursor,
+ off_t offset,
+ unsigned int *left)
+{
+ struct pack_window *win = *w_cursor;
+
+ if (p->pack_fd == -1 && open_packed_git(p))
+ die("packfile %s cannot be accessed", p->pack_name);
+
+ /* Since packfiles end in a hash of their content and its
+ * pointless to ask for an offset into the middle of that
+ * hash, and the in_window function above wouldn't match
+ * don't allow an offset too close to the end of the file.
+ */
+ if (offset > (p->pack_size - 20))
+ die("offset beyond end of packfile (truncated pack?)");
+
+ if (!win || !in_window(win, offset)) {
+ if (win)
+ win->inuse_cnt--;
+ for (win = p->windows; win; win = win->next) {
+ if (in_window(win, offset))
+ break;
+ }
+ if (!win) {
+ size_t window_align = packed_git_window_size / 2;
+ off_t len;
+ win = xcalloc(1, sizeof(*win));
+ win->offset = (offset / window_align) * window_align;
+ len = p->pack_size - win->offset;
+ if (len > packed_git_window_size)
+ len = packed_git_window_size;
+ win->len = (size_t)len;
+ pack_mapped += win->len;
+ while (packed_git_limit < pack_mapped
+ && unuse_one_window(p, p->pack_fd))
+ ; /* nothing */
+ win->base = xmmap(NULL, win->len,
+ PROT_READ, MAP_PRIVATE,
+ p->pack_fd, win->offset);
+ if (win->base == MAP_FAILED)
+ die("packfile %s cannot be mapped: %s",
+ p->pack_name,
+ strerror(errno));
+ pack_mmap_calls++;
+ pack_open_windows++;
+ if (pack_mapped > peak_pack_mapped)
+ peak_pack_mapped = pack_mapped;
+ if (pack_open_windows > peak_pack_open_windows)
+ peak_pack_open_windows = pack_open_windows;
+ win->next = p->windows;
+ p->windows = win;
+ }
+ }
+ if (win != *w_cursor) {
+ win->last_used = pack_used_ctr++;
+ win->inuse_cnt++;
+ *w_cursor = win;
+ }
+ offset -= win->offset;
+ if (left)
+ *left = win->len - xsize_t(offset);
+ return win->base + offset;
+}
+
+struct packed_git *add_packed_git(const char *path, int path_len, int local)
+{
+ struct stat st;
+ struct packed_git *p = xmalloc(sizeof(*p) + path_len + 2);
+
+ /*
+ * Make sure a corresponding .pack file exists and that
+ * the index looks sane.
+ */
+ path_len -= strlen(".idx");
+ if (path_len < 1)
+ return NULL;
+ memcpy(p->pack_name, path, path_len);
+ strcpy(p->pack_name + path_len, ".pack");
+ if (stat(p->pack_name, &st) || !S_ISREG(st.st_mode)) {
+ free(p);
+ return NULL;
+ }
+
+ /* ok, it looks sane as far as we can check without
+ * actually mapping the pack file.
+ */
+ p->index_version = 0;
+ p->index_data = NULL;
+ p->index_size = 0;
+ p->num_objects = 0;
+ p->pack_size = st.st_size;
+ p->next = NULL;
+ p->windows = NULL;
+ p->pack_fd = -1;
+ p->pack_local = local;
+ p->mtime = st.st_mtime;
+ if (path_len < 40 || get_sha1_hex(path + path_len - 40, p->sha1))
+ hashclr(p->sha1);
+ return p;
+}
+
+struct packed_git *parse_pack_index(unsigned char *sha1)
+{
+ char *path = sha1_pack_index_name(sha1);
+ return parse_pack_index_file(sha1, path);
+}
+
+struct packed_git *parse_pack_index_file(const unsigned char *sha1,
+ const char *idx_path)
+{
+ const char *path = sha1_pack_name(sha1);
+ struct packed_git *p = xmalloc(sizeof(*p) + strlen(path) + 2);
+
+ if (check_packed_git_idx(idx_path, p)) {
+ free(p);
+ return NULL;
+ }
+
+ strcpy(p->pack_name, path);
+ p->pack_size = 0;
+ p->next = NULL;
+ p->windows = NULL;
+ p->pack_fd = -1;
+ hashcpy(p->sha1, sha1);
+ return p;
+}
+
+void install_packed_git(struct packed_git *pack)
+{
+ pack->next = packed_git;
+ packed_git = pack;
+}
+
+static void prepare_packed_git_one(char *objdir, int local)
+{
+ /* Ensure that this buffer is large enough so that we can
+ append "/pack/" without clobbering the stack even if
+ strlen(objdir) were PATH_MAX. */
+ char path[PATH_MAX + 1 + 4 + 1 + 1];
+ int len;
+ DIR *dir;
+ struct dirent *de;
+
+ sprintf(path, "%s/pack", objdir);
+ len = strlen(path);
+ dir = opendir(path);
+ if (!dir) {
+ if (errno != ENOENT)
+ error("unable to open object pack directory: %s: %s",
+ path, strerror(errno));
+ return;
+ }
+ path[len++] = '/';
+ while ((de = readdir(dir)) != NULL) {
+ int namelen = strlen(de->d_name);
+ struct packed_git *p;
+
+ if (!has_extension(de->d_name, ".idx"))
+ continue;
+
+ if (len + namelen + 1 > sizeof(path))
+ continue;
+
+ /* Don't reopen a pack we already have. */
+ strcpy(path + len, de->d_name);
+ for (p = packed_git; p; p = p->next) {
+ if (!memcmp(path, p->pack_name, len + namelen - 4))
+ break;
+ }
+ if (p)
+ continue;
+ /* See if it really is a valid .idx file with corresponding
+ * .pack file that we can map.
+ */
+ p = add_packed_git(path, len + namelen, local);
+ if (!p)
+ continue;
+ install_packed_git(p);
+ }
+ closedir(dir);
+}
+
+static int sort_pack(const void *a_, const void *b_)
+{
+ struct packed_git *a = *((struct packed_git **)a_);
+ struct packed_git *b = *((struct packed_git **)b_);
+ int st;
+
+ /*
+ * Local packs tend to contain objects specific to our
+ * variant of the project than remote ones. In addition,
+ * remote ones could be on a network mounted filesystem.
+ * Favor local ones for these reasons.
+ */
+ st = a->pack_local - b->pack_local;
+ if (st)
+ return -st;
+
+ /*
+ * Younger packs tend to contain more recent objects,
+ * and more recent objects tend to get accessed more
+ * often.
+ */
+ if (a->mtime < b->mtime)
+ return 1;
+ else if (a->mtime == b->mtime)
+ return 0;
+ return -1;
+}
+
+static void rearrange_packed_git(void)
+{
+ struct packed_git **ary, *p;
+ int i, n;
+
+ for (n = 0, p = packed_git; p; p = p->next)
+ n++;
+ if (n < 2)
+ return;
+
+ /* prepare an array of packed_git for easier sorting */
+ ary = xcalloc(n, sizeof(struct packed_git *));
+ for (n = 0, p = packed_git; p; p = p->next)
+ ary[n++] = p;
+
+ qsort(ary, n, sizeof(struct packed_git *), sort_pack);
+
+ /* link them back again */
+ for (i = 0; i < n - 1; i++)
+ ary[i]->next = ary[i + 1];
+ ary[n - 1]->next = NULL;
+ packed_git = ary[0];
+
+ free(ary);
+}
+
+static int prepare_packed_git_run_once = 0;
+void prepare_packed_git(void)
+{
+ struct alternate_object_database *alt;
+
+ if (prepare_packed_git_run_once)
+ return;
+ prepare_packed_git_one(get_object_directory(), 1);
+ prepare_alt_odb();
+ for (alt = alt_odb_list; alt; alt = alt->next) {
+ alt->name[-1] = 0;
+ prepare_packed_git_one(alt->base, 0);
+ alt->name[-1] = '/';
+ }
+ rearrange_packed_git();
+ prepare_packed_git_run_once = 1;
+}
+
+void reprepare_packed_git(void)
+{
+ prepare_packed_git_run_once = 0;
+ prepare_packed_git();
+}
+
+int check_sha1_signature(const unsigned char *sha1, void *map, unsigned long size, const char *type)
+{
+ unsigned char real_sha1[20];
+ hash_sha1_file(map, size, type, real_sha1);
+ return hashcmp(sha1, real_sha1) ? -1 : 0;
+}
+
+static void *map_sha1_file(const unsigned char *sha1, unsigned long *size)
+{
+ struct stat st;
+ void *map;
+ int fd;
+ char *filename = find_sha1_file(sha1, &st);
+
+ if (!filename) {
+ return NULL;
+ }
+
+ fd = open(filename, O_RDONLY | sha1_file_open_flag);
+ if (fd < 0) {
+ /* See if it works without O_NOATIME */
+ switch (sha1_file_open_flag) {
+ default:
+ fd = open(filename, O_RDONLY);
+ if (fd >= 0)
+ break;
+ /* Fallthrough */
+ case 0:
+ return NULL;
+ }
+
+ /* If it failed once, it will probably fail again.
+ * Stop using O_NOATIME
+ */
+ sha1_file_open_flag = 0;
+ }
+ *size = xsize_t(st.st_size);
+ map = xmmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+ return map;
+}
+
+static int legacy_loose_object(unsigned char *map)
+{
+ unsigned int word;
+
+ /*
+ * Is it a zlib-compressed buffer? If so, the first byte
+ * must be 0x78 (15-bit window size, deflated), and the
+ * first 16-bit word is evenly divisible by 31
+ */
+ word = (map[0] << 8) + map[1];
+ if (map[0] == 0x78 && !(word % 31))
+ return 1;
+ else
+ return 0;
+}
+
+unsigned long unpack_object_header_gently(const unsigned char *buf, unsigned long len, enum object_type *type, unsigned long *sizep)
+{
+ unsigned shift;
+ unsigned char c;
+ unsigned long size;
+ unsigned long used = 0;
+
+ c = buf[used++];
+ *type = (c >> 4) & 7;
+ size = c & 15;
+ shift = 4;
+ while (c & 0x80) {
+ if (len <= used)
+ return 0;
+ if (sizeof(long) * 8 <= shift)
+ return 0;
+ c = buf[used++];
+ size += (c & 0x7f) << shift;
+ shift += 7;
+ }
+ *sizep = size;
+ return used;
+}
+
+static int unpack_sha1_header(z_stream *stream, unsigned char *map, unsigned long mapsize, void *buffer, unsigned long bufsiz)
+{
+ unsigned long size, used;
+ static const char valid_loose_object_type[8] = {
+ 0, /* OBJ_EXT */
+ 1, 1, 1, 1, /* "commit", "tree", "blob", "tag" */
+ 0, /* "delta" and others are invalid in a loose object */
+ };
+ enum object_type type;
+
+ /* Get the data stream */
+ memset(stream, 0, sizeof(*stream));
+ stream->next_in = map;
+ stream->avail_in = mapsize;
+ stream->next_out = buffer;
+ stream->avail_out = bufsiz;
+
+ if (legacy_loose_object(map)) {
+ inflateInit(stream);
+ return inflate(stream, 0);
+ }
+
+
+ /*
+ * There used to be a second loose object header format which
+ * was meant to mimic the in-pack format, allowing for direct
+ * copy of the object data. This format turned up not to be
+ * really worth it and we don't write it any longer. But we
+ * can still read it.
+ */
+ used = unpack_object_header_gently(map, mapsize, &type, &size);
+ if (!used || !valid_loose_object_type[type])
+ return -1;
+ map += used;
+ mapsize -= used;
+
+ /* Set up the stream for the rest.. */
+ stream->next_in = map;
+ stream->avail_in = mapsize;
+ inflateInit(stream);
+
+ /* And generate the fake traditional header */
+ stream->total_out = 1 + snprintf(buffer, bufsiz, "%s %lu",
+ typename(type), size);
+ return 0;
+}
+
+static void *unpack_sha1_rest(z_stream *stream, void *buffer, unsigned long size, const unsigned char *sha1)
+{
+ int bytes = strlen(buffer) + 1;
+ unsigned char *buf = xmalloc(1+size);
+ unsigned long n;
+ int status = Z_OK;
+
+ n = stream->total_out - bytes;
+ if (n > size)
+ n = size;
+ memcpy(buf, (char *) buffer + bytes, n);
+ bytes = n;
+ if (bytes <= size) {
+ /*
+ * The above condition must be (bytes <= size), not
+ * (bytes < size). In other words, even though we
+ * expect no more output and set avail_out to zer0,
+ * the input zlib stream may have bytes that express
+ * "this concludes the stream", and we *do* want to
+ * eat that input.
+ *
+ * Otherwise we would not be able to test that we
+ * consumed all the input to reach the expected size;
+ * we also want to check that zlib tells us that all
+ * went well with status == Z_STREAM_END at the end.
+ */
+ stream->next_out = buf + bytes;
+ stream->avail_out = size - bytes;
+ while (status == Z_OK)
+ status = inflate(stream, Z_FINISH);
+ }
+ buf[size] = 0;
+ if (status == Z_STREAM_END && !stream->avail_in) {
+ inflateEnd(stream);
+ return buf;
+ }
+
+ if (status < 0)
+ error("corrupt loose object '%s'", sha1_to_hex(sha1));
+ else if (stream->avail_in)
+ error("garbage at end of loose object '%s'",
+ sha1_to_hex(sha1));
+ free(buf);
+ return NULL;
+}
+
+/*
+ * We used to just use "sscanf()", but that's actually way
+ * too permissive for what we want to check. So do an anal
+ * object header parse by hand.
+ */
+static int parse_sha1_header(const char *hdr, unsigned long *sizep)
+{
+ char type[10];
+ int i;
+ unsigned long size;
+
+ /*
+ * The type can be at most ten bytes (including the
+ * terminating '\0' that we add), and is followed by
+ * a space.
+ */
+ i = 0;
+ for (;;) {
+ char c = *hdr++;
+ if (c == ' ')
+ break;
+ type[i++] = c;
+ if (i >= sizeof(type))
+ return -1;
+ }
+ type[i] = 0;
+
+ /*
+ * The length must follow immediately, and be in canonical
+ * decimal format (ie "010" is not valid).
+ */
+ size = *hdr++ - '0';
+ if (size > 9)
+ return -1;
+ if (size) {
+ for (;;) {
+ unsigned long c = *hdr - '0';
+ if (c > 9)
+ break;
+ hdr++;
+ size = size * 10 + c;
+ }
+ }
+ *sizep = size;
+
+ /*
+ * The length must be followed by a zero byte
+ */
+ return *hdr ? -1 : type_from_string(type);
+}
+
+static void *unpack_sha1_file(void *map, unsigned long mapsize, enum object_type *type, unsigned long *size, const unsigned char *sha1)
+{
+ int ret;
+ z_stream stream;
+ char hdr[8192];
+
+ ret = unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr));
+ if (ret < Z_OK || (*type = parse_sha1_header(hdr, size)) < 0)
+ return NULL;
+
+ return unpack_sha1_rest(&stream, hdr, *size, sha1);
+}
+
+unsigned long get_size_from_delta(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t curpos)
+{
+ const unsigned char *data;
+ unsigned char delta_head[20], *in;
+ z_stream stream;
+ int st;
+
+ memset(&stream, 0, sizeof(stream));
+ stream.next_out = delta_head;
+ stream.avail_out = sizeof(delta_head);
+
+ inflateInit(&stream);
+ do {
+ in = use_pack(p, w_curs, curpos, &stream.avail_in);
+ stream.next_in = in;
+ st = inflate(&stream, Z_FINISH);
+ curpos += stream.next_in - in;
+ } while ((st == Z_OK || st == Z_BUF_ERROR) &&
+ stream.total_out < sizeof(delta_head));
+ inflateEnd(&stream);
+ if ((st != Z_STREAM_END) && stream.total_out != sizeof(delta_head))
+ die("delta data unpack-initial failed");
+
+ /* Examine the initial part of the delta to figure out
+ * the result size.
+ */
+ data = delta_head;
+
+ /* ignore base size */
+ get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
+
+ /* Read the result size */
+ return get_delta_hdr_size(&data, delta_head+sizeof(delta_head));
+}
+
+static off_t get_delta_base(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t *curpos,
+ enum object_type type,
+ off_t delta_obj_offset)
+{
+ unsigned char *base_info = use_pack(p, w_curs, *curpos, NULL);
+ off_t base_offset;
+
+ /* use_pack() assured us we have [base_info, base_info + 20)
+ * as a range that we can look at without walking off the
+ * end of the mapped window. Its actually the hash size
+ * that is assured. An OFS_DELTA longer than the hash size
+ * is stupid, as then a REF_DELTA would be smaller to store.
+ */
+ if (type == OBJ_OFS_DELTA) {
+ unsigned used = 0;
+ unsigned char c = base_info[used++];
+ base_offset = c & 127;
+ while (c & 128) {
+ base_offset += 1;
+ if (!base_offset || MSB(base_offset, 7))
+ die("offset value overflow for delta base object");
+ c = base_info[used++];
+ base_offset = (base_offset << 7) + (c & 127);
+ }
+ base_offset = delta_obj_offset - base_offset;
+ if (base_offset >= delta_obj_offset)
+ die("delta base offset out of bound");
+ *curpos += used;
+ } else if (type == OBJ_REF_DELTA) {
+ /* The base entry _must_ be in the same pack */
+ base_offset = find_pack_entry_one(base_info, p);
+ if (!base_offset)
+ die("failed to find delta-pack base object %s",
+ sha1_to_hex(base_info));
+ *curpos += 20;
+ } else
+ die("I am totally screwed");
+ return base_offset;
+}
+
+/* forward declaration for a mutually recursive function */
+static int packed_object_info(struct packed_git *p, off_t offset,
+ unsigned long *sizep);
+
+static int packed_delta_info(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t curpos,
+ enum object_type type,
+ off_t obj_offset,
+ unsigned long *sizep)
+{
+ off_t base_offset;
+
+ base_offset = get_delta_base(p, w_curs, &curpos, type, obj_offset);
+ type = packed_object_info(p, base_offset, NULL);
+
+ /* We choose to only get the type of the base object and
+ * ignore potentially corrupt pack file that expects the delta
+ * based on a base with a wrong size. This saves tons of
+ * inflate() calls.
+ */
+ if (sizep)
+ *sizep = get_size_from_delta(p, w_curs, curpos);
+
+ return type;
+}
+
+static int unpack_object_header(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t *curpos,
+ unsigned long *sizep)
+{
+ unsigned char *base;
+ unsigned int left;
+ unsigned long used;
+ enum object_type type;
+
+ /* use_pack() assures us we have [base, base + 20) available
+ * as a range that we can look at at. (Its actually the hash
+ * size that is assured.) With our object header encoding
+ * the maximum deflated object size is 2^137, which is just
+ * insane, so we know won't exceed what we have been given.
+ */
+ base = use_pack(p, w_curs, *curpos, &left);
+ used = unpack_object_header_gently(base, left, &type, sizep);
+ if (!used)
+ die("object offset outside of pack file");
+ *curpos += used;
+
+ return type;
+}
+
+const char *packed_object_info_detail(struct packed_git *p,
+ off_t obj_offset,
+ unsigned long *size,
+ unsigned long *store_size,
+ unsigned int *delta_chain_length,
+ unsigned char *base_sha1)
+{
+ struct pack_window *w_curs = NULL;
+ off_t curpos;
+ unsigned long dummy;
+ unsigned char *next_sha1;
+ enum object_type type;
+
+ *delta_chain_length = 0;
+ curpos = obj_offset;
+ type = unpack_object_header(p, &w_curs, &curpos, size);
+
+ for (;;) {
+ switch (type) {
+ default:
+ die("pack %s contains unknown object type %d",
+ p->pack_name, type);
+ case OBJ_COMMIT:
+ case OBJ_TREE:
+ case OBJ_BLOB:
+ case OBJ_TAG:
+ *store_size = 0; /* notyet */
+ unuse_pack(&w_curs);
+ return typename(type);
+ case OBJ_OFS_DELTA:
+ obj_offset = get_delta_base(p, &w_curs, &curpos, type, obj_offset);
+ if (*delta_chain_length == 0) {
+ /* TODO: find base_sha1 as pointed by curpos */
+ hashclr(base_sha1);
+ }
+ break;
+ case OBJ_REF_DELTA:
+ next_sha1 = use_pack(p, &w_curs, curpos, NULL);
+ if (*delta_chain_length == 0)
+ hashcpy(base_sha1, next_sha1);
+ obj_offset = find_pack_entry_one(next_sha1, p);
+ break;
+ }
+ (*delta_chain_length)++;
+ curpos = obj_offset;
+ type = unpack_object_header(p, &w_curs, &curpos, &dummy);
+ }
+}
+
+static int packed_object_info(struct packed_git *p, off_t obj_offset,
+ unsigned long *sizep)
+{
+ struct pack_window *w_curs = NULL;
+ unsigned long size;
+ off_t curpos = obj_offset;
+ enum object_type type;
+
+ type = unpack_object_header(p, &w_curs, &curpos, &size);
+
+ switch (type) {
+ case OBJ_OFS_DELTA:
+ case OBJ_REF_DELTA:
+ type = packed_delta_info(p, &w_curs, curpos,
+ type, obj_offset, sizep);
+ break;
+ case OBJ_COMMIT:
+ case OBJ_TREE:
+ case OBJ_BLOB:
+ case OBJ_TAG:
+ if (sizep)
+ *sizep = size;
+ break;
+ default:
+ die("pack %s contains unknown object type %d",
+ p->pack_name, type);
+ }
+ unuse_pack(&w_curs);
+ return type;
+}
+
+static void *unpack_compressed_entry(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t curpos,
+ unsigned long size)
+{
+ int st;
+ z_stream stream;
+ unsigned char *buffer, *in;
+
+ buffer = xmalloc(size + 1);
+ buffer[size] = 0;
+ memset(&stream, 0, sizeof(stream));
+ stream.next_out = buffer;
+ stream.avail_out = size;
+
+ inflateInit(&stream);
+ do {
+ in = use_pack(p, w_curs, curpos, &stream.avail_in);
+ stream.next_in = in;
+ st = inflate(&stream, Z_FINISH);
+ curpos += stream.next_in - in;
+ } while (st == Z_OK || st == Z_BUF_ERROR);
+ inflateEnd(&stream);
+ if ((st != Z_STREAM_END) || stream.total_out != size) {
+ free(buffer);
+ return NULL;
+ }
+
+ return buffer;
+}
+
+#define MAX_DELTA_CACHE (256)
+
+static size_t delta_base_cached;
+
+static struct delta_base_cache_lru_list {
+ struct delta_base_cache_lru_list *prev;
+ struct delta_base_cache_lru_list *next;
+} delta_base_cache_lru = { &delta_base_cache_lru, &delta_base_cache_lru };
+
+static struct delta_base_cache_entry {
+ struct delta_base_cache_lru_list lru;
+ void *data;
+ struct packed_git *p;
+ off_t base_offset;
+ unsigned long size;
+ enum object_type type;
+} delta_base_cache[MAX_DELTA_CACHE];
+
+static unsigned long pack_entry_hash(struct packed_git *p, off_t base_offset)
+{
+ unsigned long hash;
+
+ hash = (unsigned long)p + (unsigned long)base_offset;
+ hash += (hash >> 8) + (hash >> 16);
+ return hash % MAX_DELTA_CACHE;
+}
+
+static void *cache_or_unpack_entry(struct packed_git *p, off_t base_offset,
+ unsigned long *base_size, enum object_type *type, int keep_cache)
+{
+ void *ret;
+ unsigned long hash = pack_entry_hash(p, base_offset);
+ struct delta_base_cache_entry *ent = delta_base_cache + hash;
+
+ ret = ent->data;
+ if (ret && ent->p == p && ent->base_offset == base_offset)
+ goto found_cache_entry;
+ return unpack_entry(p, base_offset, type, base_size);
+
+found_cache_entry:
+ if (!keep_cache) {
+ ent->data = NULL;
+ ent->lru.next->prev = ent->lru.prev;
+ ent->lru.prev->next = ent->lru.next;
+ delta_base_cached -= ent->size;
+ }
+ else {
+ ret = xmalloc(ent->size + 1);
+ memcpy(ret, ent->data, ent->size);
+ ((char *)ret)[ent->size] = 0;
+ }
+ *type = ent->type;
+ *base_size = ent->size;
+ return ret;
+}
+
+static inline void release_delta_base_cache(struct delta_base_cache_entry *ent)
+{
+ if (ent->data) {
+ free(ent->data);
+ ent->data = NULL;
+ ent->lru.next->prev = ent->lru.prev;
+ ent->lru.prev->next = ent->lru.next;
+ delta_base_cached -= ent->size;
+ }
+}
+
+static void add_delta_base_cache(struct packed_git *p, off_t base_offset,
+ void *base, unsigned long base_size, enum object_type type)
+{
+ unsigned long hash = pack_entry_hash(p, base_offset);
+ struct delta_base_cache_entry *ent = delta_base_cache + hash;
+ struct delta_base_cache_lru_list *lru;
+
+ release_delta_base_cache(ent);
+ delta_base_cached += base_size;
+
+ for (lru = delta_base_cache_lru.next;
+ delta_base_cached > delta_base_cache_limit
+ && lru != &delta_base_cache_lru;
+ lru = lru->next) {
+ struct delta_base_cache_entry *f = (void *)lru;
+ if (f->type == OBJ_BLOB)
+ release_delta_base_cache(f);
+ }
+ for (lru = delta_base_cache_lru.next;
+ delta_base_cached > delta_base_cache_limit
+ && lru != &delta_base_cache_lru;
+ lru = lru->next) {
+ struct delta_base_cache_entry *f = (void *)lru;
+ release_delta_base_cache(f);
+ }
+
+ ent->p = p;
+ ent->base_offset = base_offset;
+ ent->type = type;
+ ent->data = base;
+ ent->size = base_size;
+ ent->lru.next = &delta_base_cache_lru;
+ ent->lru.prev = delta_base_cache_lru.prev;
+ delta_base_cache_lru.prev->next = &ent->lru;
+ delta_base_cache_lru.prev = &ent->lru;
+}
+
+static void *unpack_delta_entry(struct packed_git *p,
+ struct pack_window **w_curs,
+ off_t curpos,
+ unsigned long delta_size,
+ off_t obj_offset,
+ enum object_type *type,
+ unsigned long *sizep)
+{
+ void *delta_data, *result, *base;
+ unsigned long base_size;
+ off_t base_offset;
+
+ base_offset = get_delta_base(p, w_curs, &curpos, *type, obj_offset);
+ base = cache_or_unpack_entry(p, base_offset, &base_size, type, 0);
+ if (!base)
+ die("failed to read delta base object"
+ " at %"PRIuMAX" from %s",
+ (uintmax_t)base_offset, p->pack_name);
+
+ delta_data = unpack_compressed_entry(p, w_curs, curpos, delta_size);
+ result = patch_delta(base, base_size,
+ delta_data, delta_size,
+ sizep);
+ if (!result)
+ die("failed to apply delta");
+ free(delta_data);
+ add_delta_base_cache(p, base_offset, base, base_size, *type);
+ return result;
+}
+
+void *unpack_entry(struct packed_git *p, off_t obj_offset,
+ enum object_type *type, unsigned long *sizep)
+{
+ struct pack_window *w_curs = NULL;
+ off_t curpos = obj_offset;
+ void *data;
+
+ *type = unpack_object_header(p, &w_curs, &curpos, sizep);
+ switch (*type) {
+ case OBJ_OFS_DELTA:
+ case OBJ_REF_DELTA:
+ data = unpack_delta_entry(p, &w_curs, curpos, *sizep,
+ obj_offset, type, sizep);
+ break;
+ case OBJ_COMMIT:
+ case OBJ_TREE:
+ case OBJ_BLOB:
+ case OBJ_TAG:
+ data = unpack_compressed_entry(p, &w_curs, curpos, *sizep);
+ break;
+ default:
+ die("unknown object type %i in %s", *type, p->pack_name);
+ }
+ unuse_pack(&w_curs);
+ return data;
+}
+
+const unsigned char *nth_packed_object_sha1(struct packed_git *p,
+ uint32_t n)
+{
+ const unsigned char *index = p->index_data;
+ if (!index) {
+ if (open_pack_index(p))
+ return NULL;
+ index = p->index_data;
+ }
+ if (n >= p->num_objects)
+ return NULL;
+ index += 4 * 256;
+ if (p->index_version == 1) {
+ return index + 24 * n + 4;
+ } else {
+ index += 8;
+ return index + 20 * n;
+ }
+}
+
+static off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
+{
+ const unsigned char *index = p->index_data;
+ index += 4 * 256;
+ if (p->index_version == 1) {
+ return ntohl(*((uint32_t *)(index + 24 * n)));
+ } else {
+ uint32_t off;
+ index += 8 + p->num_objects * (20 + 4);
+ off = ntohl(*((uint32_t *)(index + 4 * n)));
+ if (!(off & 0x80000000))
+ return off;
+ index += p->num_objects * 4 + (off & 0x7fffffff) * 8;
+ return (((uint64_t)ntohl(*((uint32_t *)(index + 0)))) << 32) |
+ ntohl(*((uint32_t *)(index + 4)));
+ }
+}
+
+off_t find_pack_entry_one(const unsigned char *sha1,
+ struct packed_git *p)
+{
+ const uint32_t *level1_ofs = p->index_data;
+ const unsigned char *index = p->index_data;
+ unsigned hi, lo;
+
+ if (!index) {
+ if (open_pack_index(p))
+ return 0;
+ level1_ofs = p->index_data;
+ index = p->index_data;
+ }
+ if (p->index_version > 1) {
+ level1_ofs += 2;
+ index += 8;
+ }
+ index += 4 * 256;
+ hi = ntohl(level1_ofs[*sha1]);
+ lo = ((*sha1 == 0x0) ? 0 : ntohl(level1_ofs[*sha1 - 1]));
+
+ do {
+ unsigned mi = (lo + hi) / 2;
+ unsigned x = (p->index_version > 1) ? (mi * 20) : (mi * 24 + 4);
+ int cmp = hashcmp(index + x, sha1);
+ if (!cmp)
+ return nth_packed_object_offset(p, mi);
+ if (cmp > 0)
+ hi = mi;
+ else
+ lo = mi+1;
+ } while (lo < hi);
+ return 0;
+}
+
+static int matches_pack_name(struct packed_git *p, const char *ig)
+{
+ const char *last_c, *c;
+
+ if (!strcmp(p->pack_name, ig))
+ return 0;
+
+ for (c = p->pack_name, last_c = c; *c;)
+ if (*c == '/')
+ last_c = ++c;
+ else
+ ++c;
+ if (!strcmp(last_c, ig))
+ return 0;
+
+ return 1;
+}
+
+static int find_pack_entry(const unsigned char *sha1, struct pack_entry *e, const char **ignore_packed)
+{
+ static struct packed_git *last_found = (void *)1;
+ struct packed_git *p;
+ off_t offset;
+
+ prepare_packed_git();
+ if (!packed_git)
+ return 0;
+ p = (last_found == (void *)1) ? packed_git : last_found;
+
+ do {
+ if (ignore_packed) {
+ const char **ig;
+ for (ig = ignore_packed; *ig; ig++)
+ if (!matches_pack_name(p, *ig))
+ break;
+ if (*ig)
+ goto next;
+ }
+
+ offset = find_pack_entry_one(sha1, p);
+ if (offset) {
+ /*
+ * We are about to tell the caller where they can
+ * locate the requested object. We better make
+ * sure the packfile is still here and can be
+ * accessed before supplying that answer, as
+ * it may have been deleted since the index
+ * was loaded!
+ */
+ if (p->pack_fd == -1 && open_packed_git(p)) {
+ error("packfile %s cannot be accessed", p->pack_name);
+ goto next;
+ }
+ e->offset = offset;
+ e->p = p;
+ hashcpy(e->sha1, sha1);
+ last_found = p;
+ return 1;
+ }
+
+ next:
+ if (p == last_found)
+ p = packed_git;
+ else
+ p = p->next;
+ if (p == last_found)
+ p = p->next;
+ } while (p);
+ return 0;
+}
+
+struct packed_git *find_sha1_pack(const unsigned char *sha1,
+ struct packed_git *packs)
+{
+ struct packed_git *p;
+
+ for (p = packs; p; p = p->next) {
+ if (find_pack_entry_one(sha1, p))
+ return p;
+ }
+ return NULL;
+
+}
+
+static int sha1_loose_object_info(const unsigned char *sha1, unsigned long *sizep)
+{
+ int status;
+ unsigned long mapsize, size;
+ void *map;
+ z_stream stream;
+ char hdr[32];
+
+ map = map_sha1_file(sha1, &mapsize);
+ if (!map)
+ return error("unable to find %s", sha1_to_hex(sha1));
+ if (unpack_sha1_header(&stream, map, mapsize, hdr, sizeof(hdr)) < 0)
+ status = error("unable to unpack %s header",
+ sha1_to_hex(sha1));
+ else if ((status = parse_sha1_header(hdr, &size)) < 0)
+ status = error("unable to parse %s header", sha1_to_hex(sha1));
+ else if (sizep)
+ *sizep = size;
+ inflateEnd(&stream);
+ munmap(map, mapsize);
+ return status;
+}
+
+int sha1_object_info(const unsigned char *sha1, unsigned long *sizep)
+{
+ struct pack_entry e;
+
+ if (!find_pack_entry(sha1, &e, NULL)) {
+ reprepare_packed_git();
+ if (!find_pack_entry(sha1, &e, NULL))
+ return sha1_loose_object_info(sha1, sizep);
+ }
+ return packed_object_info(e.p, e.offset, sizep);
+}
+
+static void *read_packed_sha1(const unsigned char *sha1,
+ enum object_type *type, unsigned long *size)
+{
+ struct pack_entry e;
+
+ if (!find_pack_entry(sha1, &e, NULL))
+ return NULL;
+ else
+ return cache_or_unpack_entry(e.p, e.offset, size, type, 1);
+}
+
+/*
+ * This is meant to hold a *small* number of objects that you would
+ * want read_sha1_file() to be able to return, but yet you do not want
+ * to write them into the object store (e.g. a browse-only
+ * application).
+ */
+static struct cached_object {
+ unsigned char sha1[20];
+ enum object_type type;
+ void *buf;
+ unsigned long size;
+} *cached_objects;
+static int cached_object_nr, cached_object_alloc;
+
+static struct cached_object *find_cached_object(const unsigned char *sha1)
+{
+ int i;
+ struct cached_object *co = cached_objects;
+
+ for (i = 0; i < cached_object_nr; i++, co++) {
+ if (!hashcmp(co->sha1, sha1))
+ return co;
+ }
+ return NULL;
+}
+
+int pretend_sha1_file(void *buf, unsigned long len, enum object_type type,
+ unsigned char *sha1)
+{
+ struct cached_object *co;
+
+ hash_sha1_file(buf, len, typename(type), sha1);
+ if (has_sha1_file(sha1) || find_cached_object(sha1))
+ return 0;
+ if (cached_object_alloc <= cached_object_nr) {
+ cached_object_alloc = alloc_nr(cached_object_alloc);
+ cached_objects = xrealloc(cached_objects,
+ sizeof(*cached_objects) *
+ cached_object_alloc);
+ }
+ co = &cached_objects[cached_object_nr++];
+ co->size = len;
+ co->type = type;
+ co->buf = xmalloc(len);
+ memcpy(co->buf, buf, len);
+ hashcpy(co->sha1, sha1);
+ return 0;
+}
+
+void *read_sha1_file(const unsigned char *sha1, enum object_type *type,
+ unsigned long *size)
+{
+ unsigned long mapsize;
+ void *map, *buf;
+ struct cached_object *co;
+
+ co = find_cached_object(sha1);
+ if (co) {
+ buf = xmalloc(co->size + 1);
+ memcpy(buf, co->buf, co->size);
+ ((char*)buf)[co->size] = 0;
+ *type = co->type;
+ *size = co->size;
+ return buf;
+ }
+
+ buf = read_packed_sha1(sha1, type, size);
+ if (buf)
+ return buf;
+ map = map_sha1_file(sha1, &mapsize);
+ if (map) {
+ buf = unpack_sha1_file(map, mapsize, type, size, sha1);
+ munmap(map, mapsize);
+ return buf;
+ }
+ reprepare_packed_git();
+ return read_packed_sha1(sha1, type, size);
+}
+
+void *read_object_with_reference(const unsigned char *sha1,
+ const char *required_type_name,
+ unsigned long *size,
+ unsigned char *actual_sha1_return)
+{
+ enum object_type type, required_type;
+ void *buffer;
+ unsigned long isize;
+ unsigned char actual_sha1[20];
+
+ required_type = type_from_string(required_type_name);
+ hashcpy(actual_sha1, sha1);
+ while (1) {
+ int ref_length = -1;
+ const char *ref_type = NULL;
+
+ buffer = read_sha1_file(actual_sha1, &type, &isize);
+ if (!buffer)
+ return NULL;
+ if (type == required_type) {
+ *size = isize;
+ if (actual_sha1_return)
+ hashcpy(actual_sha1_return, actual_sha1);
+ return buffer;
+ }
+ /* Handle references */
+ else if (type == OBJ_COMMIT)
+ ref_type = "tree ";
+ else if (type == OBJ_TAG)
+ ref_type = "object ";
+ else {
+ free(buffer);
+ return NULL;
+ }
+ ref_length = strlen(ref_type);
+
+ if (memcmp(buffer, ref_type, ref_length) ||
+ get_sha1_hex((char *) buffer + ref_length, actual_sha1)) {
+ free(buffer);
+ return NULL;
+ }
+ free(buffer);
+ /* Now we have the ID of the referred-to object in
+ * actual_sha1. Check again. */
+ }
+}
+
+static void write_sha1_file_prepare(const void *buf, unsigned long len,
+ const char *type, unsigned char *sha1,
+ char *hdr, int *hdrlen)
+{
+ SHA_CTX c;
+
+ /* Generate the header */
+ *hdrlen = sprintf(hdr, "%s %lu", type, len)+1;
+
+ /* Sha1.. */
+ SHA1_Init(&c);
+ SHA1_Update(&c, hdr, *hdrlen);
+ SHA1_Update(&c, buf, len);
+ SHA1_Final(sha1, &c);
+}
+
+/*
+ * Link the tempfile to the final place, possibly creating the
+ * last directory level as you do so.
+ *
+ * Returns the errno on failure, 0 on success.
+ */
+static int link_temp_to_file(const char *tmpfile, const char *filename)
+{
+ int ret;
+ char *dir;
+
+ if (!link(tmpfile, filename))
+ return 0;
+
+ /*
+ * Try to mkdir the last path component if that failed.
+ *
+ * Re-try the "link()" regardless of whether the mkdir
+ * succeeds, since a race might mean that somebody
+ * else succeeded.
+ */
+ ret = errno;
+ dir = strrchr(filename, '/');
+ if (dir) {
+ *dir = 0;
+ if (!mkdir(filename, 0777) && adjust_shared_perm(filename)) {
+ *dir = '/';
+ return -2;
+ }
+ *dir = '/';
+ if (!link(tmpfile, filename))
+ return 0;
+ ret = errno;
+ }
+ return ret;
+}
+
+/*
+ * Move the just written object into its final resting place
+ */
+int move_temp_to_file(const char *tmpfile, const char *filename)
+{
+ int ret = link_temp_to_file(tmpfile, filename);
+
+ /*
+ * Coda hack - coda doesn't like cross-directory links,
+ * so we fall back to a rename, which will mean that it
+ * won't be able to check collisions, but that's not a
+ * big deal.
+ *
+ * The same holds for FAT formatted media.
+ *
+ * When this succeeds, we just return 0. We have nothing
+ * left to unlink.
+ */
+ if (ret && ret != EEXIST) {
+ if (!rename(tmpfile, filename))
+ return 0;
+ ret = errno;
+ }
+ unlink(tmpfile);
+ if (ret) {
+ if (ret != EEXIST) {
+ return error("unable to write sha1 filename %s: %s\n", filename, strerror(ret));
+ }
+ /* FIXME!!! Collision check here ? */
+ }
+
+ return 0;
+}
+
+static int write_buffer(int fd, const void *buf, size_t len)
+{
+ if (write_in_full(fd, buf, len) < 0)
+ return error("file write error (%s)", strerror(errno));
+ return 0;
+}
+
+int hash_sha1_file(const void *buf, unsigned long len, const char *type,
+ unsigned char *sha1)
+{
+ char hdr[32];
+ int hdrlen;
+ write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
+ return 0;
+}
+
+int write_sha1_file(void *buf, unsigned long len, const char *type, unsigned char *returnsha1)
+{
+ int size, ret;
+ unsigned char *compressed;
+ z_stream stream;
+ unsigned char sha1[20];
+ char *filename;
+ static char tmpfile[PATH_MAX];
+ char hdr[32];
+ int fd, hdrlen;
+
+ /* Normally if we have it in the pack then we do not bother writing
+ * it out into .git/objects/??/?{38} file.
+ */
+ write_sha1_file_prepare(buf, len, type, sha1, hdr, &hdrlen);
+ filename = sha1_file_name(sha1);
+ if (returnsha1)
+ hashcpy(returnsha1, sha1);
+ if (has_sha1_file(sha1))
+ return 0;
+ fd = open(filename, O_RDONLY);
+ if (fd >= 0) {
+ /*
+ * FIXME!!! We might do collision checking here, but we'd
+ * need to uncompress the old file and check it. Later.
+ */
+ close(fd);
+ return 0;
+ }
+
+ if (errno != ENOENT) {
+ return error("sha1 file %s: %s\n", filename, strerror(errno));
+ }
+
+ snprintf(tmpfile, sizeof(tmpfile), "%s/tmp_obj_XXXXXX", get_object_directory());
+
+ fd = mkstemp(tmpfile);
+ if (fd < 0) {
+ if (errno == EPERM)
+ return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
+ else
+ return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
+ }
+
+ /* Set it up */
+ memset(&stream, 0, sizeof(stream));
+ deflateInit(&stream, zlib_compression_level);
+ size = 8 + deflateBound(&stream, len+hdrlen);
+ compressed = xmalloc(size);
+
+ /* Compress it */
+ stream.next_out = compressed;
+ stream.avail_out = size;
+
+ /* First header.. */
+ stream.next_in = (unsigned char *)hdr;
+ stream.avail_in = hdrlen;
+ while (deflate(&stream, 0) == Z_OK)
+ /* nothing */;
+
+ /* Then the data itself.. */
+ stream.next_in = buf;
+ stream.avail_in = len;
+ ret = deflate(&stream, Z_FINISH);
+ if (ret != Z_STREAM_END)
+ die("unable to deflate new object %s (%d)", sha1_to_hex(sha1), ret);
+
+ ret = deflateEnd(&stream);
+ if (ret != Z_OK)
+ die("deflateEnd on object %s failed (%d)", sha1_to_hex(sha1), ret);
+
+ size = stream.total_out;
+
+ if (write_buffer(fd, compressed, size) < 0)
+ die("unable to write sha1 file");
+ fchmod(fd, 0444);
+ if (close(fd))
+ die("unable to write sha1 file");
+ free(compressed);
+
+ return move_temp_to_file(tmpfile, filename);
+}
+
+/*
+ * We need to unpack and recompress the object for writing
+ * it out to a different file.
+ */
+static void *repack_object(const unsigned char *sha1, unsigned long *objsize)
+{
+ size_t size;
+ z_stream stream;
+ unsigned char *unpacked;
+ unsigned long len;
+ enum object_type type;
+ char hdr[32];
+ int hdrlen;
+ void *buf;
+
+ /* need to unpack and recompress it by itself */
+ unpacked = read_packed_sha1(sha1, &type, &len);
+ if (!unpacked)
+ error("cannot read sha1_file for %s", sha1_to_hex(sha1));
+
+ hdrlen = sprintf(hdr, "%s %lu", typename(type), len) + 1;
+
+ /* Set it up */
+ memset(&stream, 0, sizeof(stream));
+ deflateInit(&stream, zlib_compression_level);
+ size = deflateBound(&stream, len + hdrlen);
+ buf = xmalloc(size);
+
+ /* Compress it */
+ stream.next_out = buf;
+ stream.avail_out = size;
+
+ /* First header.. */
+ stream.next_in = (void *)hdr;
+ stream.avail_in = hdrlen;
+ while (deflate(&stream, 0) == Z_OK)
+ /* nothing */;
+
+ /* Then the data itself.. */
+ stream.next_in = unpacked;
+ stream.avail_in = len;
+ while (deflate(&stream, Z_FINISH) == Z_OK)
+ /* nothing */;
+ deflateEnd(&stream);
+ free(unpacked);
+
+ *objsize = stream.total_out;
+ return buf;
+}
+
+int write_sha1_to_fd(int fd, const unsigned char *sha1)
+{
+ int retval;
+ unsigned long objsize;
+ void *buf = map_sha1_file(sha1, &objsize);
+
+ if (buf) {
+ retval = write_buffer(fd, buf, objsize);
+ munmap(buf, objsize);
+ return retval;
+ }
+
+ buf = repack_object(sha1, &objsize);
+ retval = write_buffer(fd, buf, objsize);
+ free(buf);
+ return retval;
+}
+
+int write_sha1_from_fd(const unsigned char *sha1, int fd, char *buffer,
+ size_t bufsize, size_t *bufposn)
+{
+ char tmpfile[PATH_MAX];
+ int local;
+ z_stream stream;
+ unsigned char real_sha1[20];
+ unsigned char discard[4096];
+ int ret;
+ SHA_CTX c;
+
+ snprintf(tmpfile, sizeof(tmpfile), "%s/tmp_obj_XXXXXX", get_object_directory());
+
+ local = mkstemp(tmpfile);
+ if (local < 0) {
+ if (errno == EPERM)
+ return error("insufficient permission for adding an object to repository database %s\n", get_object_directory());
+ else
+ return error("unable to create temporary sha1 filename %s: %s\n", tmpfile, strerror(errno));
+ }
+
+ memset(&stream, 0, sizeof(stream));
+
+ inflateInit(&stream);
+
+ SHA1_Init(&c);
+
+ do {
+ ssize_t size;
+ if (*bufposn) {
+ stream.avail_in = *bufposn;
+ stream.next_in = (unsigned char *) buffer;
+ do {
+ stream.next_out = discard;
+ stream.avail_out = sizeof(discard);
+ ret = inflate(&stream, Z_SYNC_FLUSH);
+ SHA1_Update(&c, discard, sizeof(discard) -
+ stream.avail_out);
+ } while (stream.avail_in && ret == Z_OK);
+ if (write_buffer(local, buffer, *bufposn - stream.avail_in) < 0)
+ die("unable to write sha1 file");
+ memmove(buffer, buffer + *bufposn - stream.avail_in,
+ stream.avail_in);
+ *bufposn = stream.avail_in;
+ if (ret != Z_OK)
+ break;
+ }
+ size = xread(fd, buffer + *bufposn, bufsize - *bufposn);
+ if (size <= 0) {
+ close(local);
+ unlink(tmpfile);
+ if (!size)
+ return error("Connection closed?");
+ perror("Reading from connection");
+ return -1;
+ }
+ *bufposn += size;
+ } while (1);
+ inflateEnd(&stream);
+
+ fchmod(local, 0444);
+ if (close(local) != 0)
+ die("unable to write sha1 file");
+ SHA1_Final(real_sha1, &c);
+ if (ret != Z_STREAM_END) {
+ unlink(tmpfile);
+ return error("File %s corrupted", sha1_to_hex(sha1));
+ }
+ if (hashcmp(sha1, real_sha1)) {
+ unlink(tmpfile);
+ return error("File %s has bad hash", sha1_to_hex(sha1));
+ }
+
+ return move_temp_to_file(tmpfile, sha1_file_name(sha1));
+}
+
+int has_pack_index(const unsigned char *sha1)
+{
+ struct stat st;
+ if (stat(sha1_pack_index_name(sha1), &st))
+ return 0;
+ return 1;
+}
+
+int has_pack_file(const unsigned char *sha1)
+{
+ struct stat st;
+ if (stat(sha1_pack_name(sha1), &st))
+ return 0;
+ return 1;
+}
+
+int has_sha1_pack(const unsigned char *sha1, const char **ignore_packed)
+{
+ struct pack_entry e;
+ return find_pack_entry(sha1, &e, ignore_packed);
+}
+
+int has_sha1_file(const unsigned char *sha1)
+{
+ struct stat st;
+ struct pack_entry e;
+
+ if (find_pack_entry(sha1, &e, NULL))
+ return 1;
+ return find_sha1_file(sha1, &st) ? 1 : 0;
+}
+
+/*
+ * reads from fd as long as possible into a supplied buffer of size bytes.
+ * If necessary the buffer's size is increased using realloc()
+ *
+ * returns 0 if anything went fine and -1 otherwise
+ *
+ * The buffer is always NUL-terminated, not including it in returned size.
+ *
+ * NOTE: both buf and size may change, but even when -1 is returned
+ * you still have to free() it yourself.
+ */
+int read_fd(int fd, char **return_buf, unsigned long *return_size)
+{
+ char *buf = *return_buf;
+ unsigned long size = *return_size;
+ ssize_t iret;
+ unsigned long off = 0;
+
+ if (!buf || size <= 1) {
+ size = 1024;
+ buf = xrealloc(buf, size);
+ }
+
+ do {
+ iret = xread(fd, buf + off, (size - 1) - off);
+ if (iret > 0) {
+ off += iret;
+ if (off == size - 1) {
+ size = alloc_nr(size);
+ buf = xrealloc(buf, size);
+ }
+ }
+ } while (iret > 0);
+
+ buf[off] = '\0';
+
+ *return_buf = buf;
+ *return_size = off;
+
+ if (iret < 0)
+ return -1;
+ return 0;
+}
+
+int index_pipe(unsigned char *sha1, int fd, const char *type, int write_object)
+{
+ unsigned long size = 4096;
+ char *buf = xmalloc(size);
+ int ret;
+
+ if (read_fd(fd, &buf, &size)) {
+ free(buf);
+ return -1;
+ }
+
+ if (!type)
+ type = blob_type;
+ if (write_object)
+ ret = write_sha1_file(buf, size, type, sha1);
+ else
+ ret = hash_sha1_file(buf, size, type, sha1);
+ free(buf);
+ return ret;
+}
+
+int index_fd(unsigned char *sha1, int fd, struct stat *st, int write_object,
+ enum object_type type, const char *path)
+{
+ size_t size = xsize_t(st->st_size);
+ void *buf = NULL;
+ int ret, re_allocated = 0;
+
+ if (size)
+ buf = xmmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
+ close(fd);
+
+ if (!type)
+ type = OBJ_BLOB;
+
+ /*
+ * Convert blobs to git internal format
+ */
+ if ((type == OBJ_BLOB) && S_ISREG(st->st_mode)) {
+ unsigned long nsize = size;
+ char *nbuf = convert_to_git(path, buf, &nsize);
+ if (nbuf) {
+ munmap(buf, size);
+ size = nsize;
+ buf = nbuf;
+ re_allocated = 1;
+ }
+ }
+
+ if (write_object)
+ ret = write_sha1_file(buf, size, typename(type), sha1);
+ else
+ ret = hash_sha1_file(buf, size, typename(type), sha1);
+ if (re_allocated) {
+ free(buf);
+ return ret;
+ }
+ if (size)
+ munmap(buf, size);
+ return ret;
+}
+
+int index_path(unsigned char *sha1, const char *path, struct stat *st, int write_object)
+{
+ int fd;
+ char *target;
+ size_t len;
+
+ switch (st->st_mode & S_IFMT) {
+ case S_IFREG:
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ return error("open(\"%s\"): %s", path,
+ strerror(errno));
+ if (index_fd(sha1, fd, st, write_object, OBJ_BLOB, path) < 0)
+ return error("%s: failed to insert into database",
+ path);
+ break;
+ case S_IFLNK:
+ len = xsize_t(st->st_size);
+ target = xmalloc(len + 1);
+ if (readlink(path, target, len + 1) != st->st_size) {
+ char *errstr = strerror(errno);
+ free(target);
+ return error("readlink(\"%s\"): %s", path,
+ errstr);
+ }
+ if (!write_object)
+ hash_sha1_file(target, len, blob_type, sha1);
+ else if (write_sha1_file(target, len, blob_type, sha1))
+ return error("%s: failed to insert into database",
+ path);
+ free(target);
+ break;
+ case S_IFDIR:
+ return resolve_gitlink_ref(path, "HEAD", sha1);
+ default:
+ return error("%s: unsupported file type", path);
+ }
+ return 0;
+}
+
+int read_pack_header(int fd, struct pack_header *header)
+{
+ char *c = (char*)header;
+ ssize_t remaining = sizeof(struct pack_header);
+ do {
+ ssize_t r = xread(fd, c, remaining);
+ if (r <= 0)
+ /* "eof before pack header was fully read" */
+ return PH_ERROR_EOF;
+ remaining -= r;
+ c += r;
+ } while (remaining > 0);
+ if (header->hdr_signature != htonl(PACK_SIGNATURE))
+ /* "protocol error (pack signature mismatch detected)" */
+ return PH_ERROR_PACK_SIGNATURE;
+ if (!pack_version_ok(header->hdr_version))
+ /* "protocol error (pack version unsupported)" */
+ return PH_ERROR_PROTOCOL;
+ return 0;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-18 20:32:53 +0000