diff options
Diffstat (limited to 'wrapper.c')
| -rw-r--r-- | wrapper.c | 469 |
1 files changed, 357 insertions, 112 deletions
@@ -3,11 +3,46 @@ */ #include "cache.h" +static void do_nothing(size_t size) +{ +} + +static void (*try_to_free_routine)(size_t size) = do_nothing; + +static int memory_limit_check(size_t size, int gentle) +{ + static size_t limit = 0; + if (!limit) { + limit = git_env_ulong("GIT_ALLOC_LIMIT", 0); + if (!limit) + limit = SIZE_MAX; + } + if (size > limit) { + if (gentle) { + error("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX, + (uintmax_t)size, (uintmax_t)limit); + return -1; + } else + die("attempting to allocate %"PRIuMAX" over limit %"PRIuMAX, + (uintmax_t)size, (uintmax_t)limit); + } + return 0; +} + +try_to_free_t set_try_to_free_routine(try_to_free_t routine) +{ + try_to_free_t old = try_to_free_routine; + if (!routine) + routine = do_nothing; + try_to_free_routine = routine; + return old; +} + char *xstrdup(const char *str) { char *ret = strdup(str); if (!ret) { - release_pack_memory(strlen(str) + 1, -1); + try_to_free_routine(strlen(str) + 1); ret = strdup(str); if (!ret) die("Out of memory, strdup failed"); @@ -15,18 +50,30 @@ char *xstrdup(const char *str) return ret; } -void *xmalloc(size_t size) +static void *do_xmalloc(size_t size, int gentle) { - void *ret = malloc(size); + void *ret; + + if (memory_limit_check(size, gentle)) + return NULL; + ret = malloc(size); if (!ret && !size) ret = malloc(1); if (!ret) { - release_pack_memory(size, -1); + try_to_free_routine(size); ret = malloc(size); if (!ret && !size) ret = malloc(1); - if (!ret) - die("Out of memory, malloc failed"); + if (!ret) { + if (!gentle) + die("Out of memory, malloc failed (tried to allocate %lu bytes)", + (unsigned long)size); + else { + error("Out of memory, malloc failed (tried to allocate %lu bytes)", + (unsigned long)size); + return NULL; + } + } } #ifdef XMALLOC_POISON memset(ret, 0xA5, size); @@ -34,6 +81,37 @@ void *xmalloc(size_t size) return ret; } +void *xmalloc(size_t size) +{ + return do_xmalloc(size, 0); +} + +static void *do_xmallocz(size_t size, int gentle) +{ + void *ret; + if (unsigned_add_overflows(size, 1)) { + if (gentle) { + error("Data too large to fit into virtual memory space."); + return NULL; + } else + die("Data too large to fit into virtual memory space."); + } + ret = do_xmalloc(size + 1, gentle); + if (ret) + ((char*)ret)[size] = 0; + return ret; +} + +void *xmallocz(size_t size) +{ + return do_xmallocz(size, 0); +} + +void *xmallocz_gently(size_t size) +{ + return do_xmallocz(size, 1); +} + /* * xmemdupz() allocates (len + 1) bytes of memory, duplicates "len" bytes of * "data" to the allocated memory, zero terminates the allocated memory, @@ -42,10 +120,7 @@ void *xmalloc(size_t size) */ void *xmemdupz(const void *data, size_t len) { - char *p = xmalloc(len + 1); - memcpy(p, data, len); - p[len] = '\0'; - return p; + return memcpy(xmallocz(len), data, len); } char *xstrndup(const char *str, size_t len) @@ -56,11 +131,14 @@ char *xstrndup(const char *str, size_t len) void *xrealloc(void *ptr, size_t size) { - void *ret = realloc(ptr, size); + void *ret; + + memory_limit_check(size, 0); + ret = realloc(ptr, size); if (!ret && !size) ret = realloc(ptr, 1); if (!ret) { - release_pack_memory(size, -1); + try_to_free_routine(size); ret = realloc(ptr, size); if (!ret && !size) ret = realloc(ptr, 1); @@ -72,11 +150,14 @@ void *xrealloc(void *ptr, size_t size) void *xcalloc(size_t nmemb, size_t size) { - void *ret = calloc(nmemb, size); + void *ret; + + memory_limit_check(size * nmemb, 0); + ret = calloc(nmemb, size); if (!ret && (!nmemb || !size)) ret = calloc(1, 1); if (!ret) { - release_pack_memory(nmemb * size, -1); + try_to_free_routine(nmemb * size); ret = calloc(nmemb, size); if (!ret && (!nmemb || !size)) ret = calloc(1, 1); @@ -86,20 +167,13 @@ void *xcalloc(size_t nmemb, size_t size) return ret; } -void *xmmap(void *start, size_t length, - int prot, int flags, int fd, off_t offset) -{ - void *ret = mmap(start, length, prot, flags, fd, offset); - if (ret == MAP_FAILED) { - if (!length) - return NULL; - release_pack_memory(length, fd); - ret = mmap(start, length, prot, flags, fd, offset); - if (ret == MAP_FAILED) - die_errno("Out of memory? mmap failed"); - } - return ret; -} +/* + * Limit size of IO chunks, because huge chunks only cause pain. OS X + * 64-bit is buggy, returning EINVAL if len >= INT_MAX; and even in + * the absence of bugs, large chunks can result in bad latencies when + * you decide to kill the process. + */ +#define MAX_IO_SIZE (8*1024*1024) /* * xread() is the same a read(), but it automatically restarts read() @@ -109,6 +183,8 @@ void *xmmap(void *start, size_t length, ssize_t xread(int fd, void *buf, size_t len) { ssize_t nr; + if (len > MAX_IO_SIZE) + len = MAX_IO_SIZE; while (1) { nr = read(fd, buf, len); if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) @@ -125,6 +201,8 @@ ssize_t xread(int fd, void *buf, size_t len) ssize_t xwrite(int fd, const void *buf, size_t len) { ssize_t nr; + if (len > MAX_IO_SIZE) + len = MAX_IO_SIZE; while (1) { nr = write(fd, buf, len); if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) @@ -133,6 +211,24 @@ ssize_t xwrite(int fd, const void *buf, size_t len) } } +/* + * xpread() is the same as pread(), but it automatically restarts pread() + * operations with a recoverable error (EAGAIN and EINTR). xpread() DOES + * NOT GUARANTEE that "len" bytes is read even if the data is available. + */ +ssize_t xpread(int fd, void *buf, size_t len, off_t offset) +{ + ssize_t nr; + if (len > MAX_IO_SIZE) + len = MAX_IO_SIZE; + while (1) { + nr = pread(fd, buf, len, offset); + if ((nr < 0) && (errno == EAGAIN || errno == EINTR)) + continue; + return nr; + } +} + ssize_t read_in_full(int fd, void *buf, size_t count) { char *p = buf; @@ -140,8 +236,10 @@ ssize_t read_in_full(int fd, void *buf, size_t count) while (count > 0) { ssize_t loaded = xread(fd, p, count); - if (loaded <= 0) - return total ? total : loaded; + if (loaded < 0) + return -1; + if (loaded == 0) + return total; count -= loaded; p += loaded; total += loaded; @@ -171,6 +269,26 @@ ssize_t write_in_full(int fd, const void *buf, size_t count) return total; } +ssize_t pread_in_full(int fd, void *buf, size_t count, off_t offset) +{ + char *p = buf; + ssize_t total = 0; + + while (count > 0) { + ssize_t loaded = xpread(fd, p, count, offset); + if (loaded < 0) + return -1; + if (loaded == 0) + return total; + count -= loaded; + p += loaded; + total += loaded; + offset += loaded; + } + + return total; +} + int xdup(int fd) { int ret = dup(fd); @@ -190,118 +308,245 @@ FILE *xfdopen(int fd, const char *mode) int xmkstemp(char *template) { int fd; + char origtemplate[PATH_MAX]; + strlcpy(origtemplate, template, sizeof(origtemplate)); fd = mkstemp(template); - if (fd < 0) - die_errno("Unable to create temporary file"); + if (fd < 0) { + int saved_errno = errno; + const char *nonrelative_template; + + if (strlen(template) != strlen(origtemplate)) + template = origtemplate; + + nonrelative_template = absolute_path(template); + errno = saved_errno; + die_errno("Unable to create temporary file '%s'", + nonrelative_template); + } return fd; } -/* - * zlib wrappers to make sure we don't silently miss errors - * at init time. - */ -void git_inflate_init(z_streamp strm) -{ - const char *err; - - switch (inflateInit(strm)) { - case Z_OK: - return; - - case Z_MEM_ERROR: - err = "out of memory"; - break; - case Z_VERSION_ERROR: - err = "wrong version"; - break; - default: - err = "error"; +/* git_mkstemp() - create tmp file honoring TMPDIR variable */ +int git_mkstemp(char *path, size_t len, const char *template) +{ + const char *tmp; + size_t n; + + tmp = getenv("TMPDIR"); + if (!tmp) + tmp = "/tmp"; + n = snprintf(path, len, "%s/%s", tmp, template); + if (len <= n) { + errno = ENAMETOOLONG; + return -1; } - die("inflateInit: %s (%s)", err, strm->msg ? strm->msg : "no message"); + return mkstemp(path); } -void git_inflate_end(z_streamp strm) +/* git_mkstemps() - create tmp file with suffix honoring TMPDIR variable. */ +int git_mkstemps(char *path, size_t len, const char *template, int suffix_len) { - if (inflateEnd(strm) != Z_OK) - error("inflateEnd: %s", strm->msg ? strm->msg : "failed"); + const char *tmp; + size_t n; + + tmp = getenv("TMPDIR"); + if (!tmp) + tmp = "/tmp"; + n = snprintf(path, len, "%s/%s", tmp, template); + if (len <= n) { + errno = ENAMETOOLONG; + return -1; + } + return mkstemps(path, suffix_len); } -int git_inflate(z_streamp strm, int flush) -{ - int ret = inflate(strm, flush); - const char *err; +/* Adapted from libiberty's mkstemp.c. */ - switch (ret) { - /* Out of memory is fatal. */ - case Z_MEM_ERROR: - die("inflate: out of memory"); +#undef TMP_MAX +#define TMP_MAX 16384 - /* Data corruption errors: we may want to recover from them (fsck) */ - case Z_NEED_DICT: - err = "needs dictionary"; break; - case Z_DATA_ERROR: - err = "data stream error"; break; - case Z_STREAM_ERROR: - err = "stream consistency error"; break; - default: - err = "unknown error"; break; +int git_mkstemps_mode(char *pattern, int suffix_len, int mode) +{ + static const char letters[] = + "abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "0123456789"; + static const int num_letters = 62; + uint64_t value; + struct timeval tv; + char *template; + size_t len; + int fd, count; + + len = strlen(pattern); + + if (len < 6 + suffix_len) { + errno = EINVAL; + return -1; + } - /* Z_BUF_ERROR: normal, needs more space in the output buffer */ - case Z_BUF_ERROR: - case Z_OK: - case Z_STREAM_END: - return ret; + if (strncmp(&pattern[len - 6 - suffix_len], "XXXXXX", 6)) { + errno = EINVAL; + return -1; } - error("inflate: %s (%s)", err, strm->msg ? strm->msg : "no message"); - return ret; + + /* + * Replace pattern's XXXXXX characters with randomness. + * Try TMP_MAX different filenames. + */ + gettimeofday(&tv, NULL); + value = ((size_t)(tv.tv_usec << 16)) ^ tv.tv_sec ^ getpid(); + template = &pattern[len - 6 - suffix_len]; + for (count = 0; count < TMP_MAX; ++count) { + uint64_t v = value; + /* Fill in the random bits. */ + template[0] = letters[v % num_letters]; v /= num_letters; + template[1] = letters[v % num_letters]; v /= num_letters; + template[2] = letters[v % num_letters]; v /= num_letters; + template[3] = letters[v % num_letters]; v /= num_letters; + template[4] = letters[v % num_letters]; v /= num_letters; + template[5] = letters[v % num_letters]; v /= num_letters; + + fd = open(pattern, O_CREAT | O_EXCL | O_RDWR, mode); + if (fd >= 0) + return fd; + /* + * Fatal error (EPERM, ENOSPC etc). + * It doesn't make sense to loop. + */ + if (errno != EEXIST) + break; + /* + * This is a random value. It is only necessary that + * the next TMP_MAX values generated by adding 7777 to + * VALUE are different with (module 2^32). + */ + value += 7777; + } + /* We return the null string if we can't find a unique file name. */ + pattern[0] = '\0'; + return -1; +} + +int git_mkstemp_mode(char *pattern, int mode) +{ + /* mkstemp is just mkstemps with no suffix */ + return git_mkstemps_mode(pattern, 0, mode); } -int odb_mkstemp(char *template, size_t limit, const char *pattern) +#ifdef NO_MKSTEMPS +int gitmkstemps(char *pattern, int suffix_len) +{ + return git_mkstemps_mode(pattern, suffix_len, 0600); +} +#endif + +int xmkstemp_mode(char *template, int mode) { int fd; + char origtemplate[PATH_MAX]; + strlcpy(origtemplate, template, sizeof(origtemplate)); - snprintf(template, limit, "%s/%s", - get_object_directory(), pattern); - fd = mkstemp(template); - if (0 <= fd) - return fd; + fd = git_mkstemp_mode(template, mode); + if (fd < 0) { + int saved_errno = errno; + const char *nonrelative_template; + + if (!template[0]) + template = origtemplate; - /* slow path */ - /* some mkstemp implementations erase template on failure */ - snprintf(template, limit, "%s/%s", - get_object_directory(), pattern); - safe_create_leading_directories(template); - return xmkstemp(template); + nonrelative_template = absolute_path(template); + errno = saved_errno; + die_errno("Unable to create temporary file '%s'", + nonrelative_template); + } + return fd; } -int odb_pack_keep(char *name, size_t namesz, unsigned char *sha1) +static int warn_if_unremovable(const char *op, const char *file, int rc) { - int fd; + int err; + if (!rc || errno == ENOENT) + return 0; + err = errno; + warning("unable to %s %s: %s", op, file, strerror(errno)); + errno = err; + return rc; +} - snprintf(name, namesz, "%s/pack/pack-%s.keep", - get_object_directory(), sha1_to_hex(sha1)); - fd = open(name, O_RDWR|O_CREAT|O_EXCL, 0600); - if (0 <= fd) - return fd; +int unlink_or_msg(const char *file, struct strbuf *err) +{ + int rc = unlink(file); + + assert(err); - /* slow path */ - safe_create_leading_directories(name); - return open(name, O_RDWR|O_CREAT|O_EXCL, 0600); + if (!rc || errno == ENOENT) + return 0; + + strbuf_addf(err, "unable to unlink %s: %s", + file, strerror(errno)); + return -1; } int unlink_or_warn(const char *file) { - int rc = unlink(file); + return warn_if_unremovable("unlink", file, unlink(file)); +} - if (rc < 0) { - int err = errno; - if (ENOENT != err) { - warning("unable to unlink %s: %s", - file, strerror(errno)); - errno = err; - } - } - return rc; +int rmdir_or_warn(const char *file) +{ + return warn_if_unremovable("rmdir", file, rmdir(file)); +} + +int remove_or_warn(unsigned int mode, const char *file) +{ + return S_ISGITLINK(mode) ? rmdir_or_warn(file) : unlink_or_warn(file); } +void warn_on_inaccessible(const char *path) +{ + warning(_("unable to access '%s': %s"), path, strerror(errno)); +} + +static int access_error_is_ok(int err, unsigned flag) +{ + return err == ENOENT || err == ENOTDIR || + ((flag & ACCESS_EACCES_OK) && err == EACCES); +} + +int access_or_warn(const char *path, int mode, unsigned flag) +{ + int ret = access(path, mode); + if (ret && !access_error_is_ok(errno, flag)) + warn_on_inaccessible(path); + return ret; +} + +int access_or_die(const char *path, int mode, unsigned flag) +{ + int ret = access(path, mode); + if (ret && !access_error_is_ok(errno, flag)) + die_errno(_("unable to access '%s'"), path); + return ret; +} + +struct passwd *xgetpwuid_self(void) +{ + struct passwd *pw; + + errno = 0; + pw = getpwuid(getuid()); + if (!pw) + die(_("unable to look up current user in the passwd file: %s"), + errno ? strerror(errno) : _("no such user")); + return pw; +} + +char *xgetcwd(void) +{ + struct strbuf sb = STRBUF_INIT; + if (strbuf_getcwd(&sb)) + die_errno(_("unable to get current working directory")); + return strbuf_detach(&sb, NULL); +} |