1 files changed, 294 insertions, 0 deletions
diff --git a/entry.c b/entry.c
new file mode 100644
index 0000000000..a4109574fa
--- /dev/null
+++ b/entry.c
@@ -0,0 +1,294 @@
+#include "cache.h"
+#include "blob.h"
+#include "dir.h"
+#include "streaming.h"
+
+static void create_directories(const char *path, int path_len,
+			       const struct checkout *state)
+{
+	char *buf = xmallocz(path_len);
+	int len = 0;
+
+	while (len < path_len) {
+		do {
+			buf[len] = path[len];
+			len++;
+		} while (len < path_len && path[len] != '/');
+		if (len >= path_len)
+			break;
+		buf[len] = 0;
+
+		/*
+		 * For 'checkout-index --prefix=<dir>', <dir> is
+		 * allowed to be a symlink to an existing directory,
+		 * and we set 'state->base_dir_len' below, such that
+		 * we test the path components of the prefix with the
+		 * stat() function instead of the lstat() function.
+		 */
+		if (has_dirs_only_path(buf, len, state->base_dir_len))
+			continue; /* ok, it is already a directory. */
+
+		/*
+		 * If this mkdir() would fail, it could be that there
+		 * is already a symlink or something else exists
+		 * there, therefore we then try to unlink it and try
+		 * one more time to create the directory.
+		 */
+		if (mkdir(buf, 0777)) {
+			if (errno == EEXIST && state->force &&
+			    !unlink_or_warn(buf) && !mkdir(buf, 0777))
+				continue;
+			die_errno("cannot create directory at '%s'", buf);
+		}
+	}
+	free(buf);
+}
+
+static void remove_subtree(struct strbuf *path)
+{
+	DIR *dir = opendir(path->buf);
+	struct dirent *de;
+	int origlen = path->len;
+
+	if (!dir)
+		die_errno("cannot opendir '%s'", path->buf);
+	while ((de = readdir(dir)) != NULL) {
+		struct stat st;
+
+		if (is_dot_or_dotdot(de->d_name))
+			continue;
+
+		strbuf_addch(path, '/');
+		strbuf_addstr(path, de->d_name);
+		if (lstat(path->buf, &st))
+			die_errno("cannot lstat '%s'", path->buf);
+		if (S_ISDIR(st.st_mode))
+			remove_subtree(path);
+		else if (unlink(path->buf))
+			die_errno("cannot unlink '%s'", path->buf);
+		strbuf_setlen(path, origlen);
+	}
+	closedir(dir);
+	if (rmdir(path->buf))
+		die_errno("cannot rmdir '%s'", path->buf);
+}
+
+static int create_file(const char *path, unsigned int mode)
+{
+	mode = (mode & 0100) ? 0777 : 0666;
+	return open(path, O_WRONLY | O_CREAT | O_EXCL, mode);
+}
+
+static void *read_blob_entry(const struct cache_entry *ce, unsigned long *size)
+{
+	enum object_type type;
+	void *new = read_sha1_file(ce->sha1, &type, size);
+
+	if (new) {
+		if (type == OBJ_BLOB)
+			return new;
+		free(new);
+	}
+	return NULL;
+}
+
+static int open_output_fd(char *path, const struct cache_entry *ce, int to_tempfile)
+{
+	int symlink = (ce->ce_mode & S_IFMT) != S_IFREG;
+	if (to_tempfile) {
+		xsnprintf(path, TEMPORARY_FILENAME_LENGTH, "%s",
+			  symlink ? ".merge_link_XXXXXX" : ".merge_file_XXXXXX");
+		return mkstemp(path);
+	} else {
+		return create_file(path, !symlink ? ce->ce_mode : 0666);
+	}
+}
+
+static int fstat_output(int fd, const struct checkout *state, struct stat *st)
+{
+	/* use fstat() only when path == ce->name */
+	if (fstat_is_reliable() &&
+	    state->refresh_cache && !state->base_dir_len) {
+		fstat(fd, st);
+		return 1;
+	}
+	return 0;
+}
+
+static int streaming_write_entry(const struct cache_entry *ce, char *path,
+				 struct stream_filter *filter,
+				 const struct checkout *state, int to_tempfile,
+				 int *fstat_done, struct stat *statbuf)
+{
+	int result = 0;
+	int fd;
+
+	fd = open_output_fd(path, ce, to_tempfile);
+	if (fd < 0)
+		return -1;
+
+	result |= stream_blob_to_fd(fd, ce->sha1, filter, 1);
+	*fstat_done = fstat_output(fd, state, statbuf);
+	result |= close(fd);
+
+	if (result)
+		unlink(path);
+	return result;
+}
+
+static int write_entry(struct cache_entry *ce,
+		       char *path, const struct checkout *state, int to_tempfile)
+{
+	unsigned int ce_mode_s_ifmt = ce->ce_mode & S_IFMT;
+	int fd, ret, fstat_done = 0;
+	char *new;
+	struct strbuf buf = STRBUF_INIT;
+	unsigned long size;
+	size_t wrote, newsize = 0;
+	struct stat st;
+
+	if (ce_mode_s_ifmt == S_IFREG) {
+		struct stream_filter *filter = get_stream_filter(ce->name, ce->sha1);
+		if (filter &&
+		    !streaming_write_entry(ce, path, filter,
+					   state, to_tempfile,
+					   &fstat_done, &st))
+			goto finish;
+	}
+
+	switch (ce_mode_s_ifmt) {
+	case S_IFREG:
+	case S_IFLNK:
+		new = read_blob_entry(ce, &size);
+		if (!new)
+			return error("unable to read sha1 file of %s (%s)",
+				path, sha1_to_hex(ce->sha1));
+
+		if (ce_mode_s_ifmt == S_IFLNK && has_symlinks && !to_tempfile) {
+			ret = symlink(new, path);
+			free(new);
+			if (ret)
+				return error("unable to create symlink %s (%s)",
+					     path, strerror(errno));
+			break;
+		}
+
+		/*
+		 * Convert from git internal format to working tree format
+		 */
+		if (ce_mode_s_ifmt == S_IFREG &&
+		    convert_to_working_tree(ce->name, new, size, &buf)) {
+			free(new);
+			new = strbuf_detach(&buf, &newsize);
+			size = newsize;
+		}
+
+		fd = open_output_fd(path, ce, to_tempfile);
+		if (fd < 0) {
+			free(new);
+			return error("unable to create file %s (%s)",
+				path, strerror(errno));
+		}
+
+		wrote = write_in_full(fd, new, size);
+		if (!to_tempfile)
+			fstat_done = fstat_output(fd, state, &st);
+		close(fd);
+		free(new);
+		if (wrote != size)
+			return error("unable to write file %s", path);
+		break;
+	case S_IFGITLINK:
+		if (to_tempfile)
+			return error("cannot create temporary submodule %s", path);
+		if (mkdir(path, 0777) < 0)
+			return error("cannot create submodule directory %s", path);
+		break;
+	default:
+		return error("unknown file mode for %s in index", path);
+	}
+
+finish:
+	if (state->refresh_cache) {
+		assert(state->istate);
+		if (!fstat_done)
+			lstat(ce->name, &st);
+		fill_stat_cache_info(ce, &st);
+		ce->ce_flags |= CE_UPDATE_IN_BASE;
+		state->istate->cache_changed |= CE_ENTRY_CHANGED;
+	}
+	return 0;
+}
+
+/*
+ * This is like 'lstat()', except it refuses to follow symlinks
+ * in the path, after skipping "skiplen".
+ */
+static int check_path(const char *path, int len, struct stat *st, int skiplen)
+{
+	const char *slash = path + len;
+
+	while (path < slash && *slash != '/')
+		slash--;
+	if (!has_dirs_only_path(path, slash - path, skiplen)) {
+		errno = ENOENT;
+		return -1;
+	}
+	return lstat(path, st);
+}
+
+/*
+ * Write the contents from ce out to the working tree.
+ *
+ * When topath[] is not NULL, instead of writing to the working tree
+ * file named by ce, a temporary file is created by this function and
+ * its name is returned in topath[], which must be able to hold at
+ * least TEMPORARY_FILENAME_LENGTH bytes long.
+ */
+int checkout_entry(struct cache_entry *ce,
+		   const struct checkout *state, char *topath)
+{
+	static struct strbuf path = STRBUF_INIT;
+	struct stat st;
+
+	if (topath)
+		return write_entry(ce, topath, state, 1);
+
+	strbuf_reset(&path);
+	strbuf_add(&path, state->base_dir, state->base_dir_len);
+	strbuf_add(&path, ce->name, ce_namelen(ce));
+
+	if (!check_path(path.buf, path.len, &st, state->base_dir_len)) {
+		unsigned changed = ce_match_stat(ce, &st, CE_MATCH_IGNORE_VALID|CE_MATCH_IGNORE_SKIP_WORKTREE);
+		if (!changed)
+			return 0;
+		if (!state->force) {
+			if (!state->quiet)
+				fprintf(stderr,
+					"%s already exists, no checkout\n",
+					path.buf);
+			return -1;
+		}
+
+		/*
+		 * We unlink the old file, to get the new one with the
+		 * right permissions (including umask, which is nasty
+		 * to emulate by hand - much easier to let the system
+		 * just do the right thing)
+		 */
+		if (S_ISDIR(st.st_mode)) {
+			/* If it is a gitlink, leave it alone! */
+			if (S_ISGITLINK(ce->ce_mode))
+				return 0;
+			if (!state->force)
+				return error("%s is a directory", path.buf);
+			remove_subtree(&path);
+		} else if (unlink(path.buf))
+			return error("unable to unlink old '%s' (%s)",
+				     path.buf, strerror(errno));
+	} else if (state->not_new)
+		return 0;
+
+	create_directories(path.buf, path.len, state);
+	return write_entry(ce, path.buf, state, 0);
+}