checkout-index: simplify locking logic

diff --git a/sha1_file.c b/sha1_file.c
index b4a67bb838d6e1a87093a90398cb254653269a86..1d1747099a31fe20f57e26fc85ec65578a01a2d1 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -398,7 +398,7 @@ static const char *parse_alt_odb_entry(const char *string,
        return end;
 }
 
-static void link_alt_odb_entries(const char *alt, int len, int sep,
+static void link_alt_odb_entries(const char *alt, int sep,
                                 const char *relative_base, int depth)
 {
        struct strbuf objdirbuf = STRBUF_INIT;
@@ -427,28 +427,19 @@ static void link_alt_odb_entries(const char *alt, int len, int sep,
 
 static void read_info_alternates(const char * relative_base, int depth)
 {
-       char *map;
-       size_t mapsz;
-       struct stat st;
        char *path;
-       int fd;
+       struct strbuf buf = STRBUF_INIT;
 
        path = xstrfmt("%s/info/alternates", relative_base);
-       fd = git_open(path);
-       free(path);
-       if (fd < 0)
-               return;
-       if (fstat(fd, &st) || (st.st_size == 0)) {
-               close(fd);
+       if (strbuf_read_file(&buf, path, 1024) < 0) {
+               warn_on_fopen_errors(path);
+               free(path);
                return;
        }
-       mapsz = xsize_t(st.st_size);
-       map = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, fd, 0);
-       close(fd);
 
-       link_alt_odb_entries(map, mapsz, '\n', relative_base, depth);
-
-       munmap(map, mapsz);
+       link_alt_odb_entries(buf.buf, '\n', relative_base, depth);
+       strbuf_release(&buf);
+       free(path);
 }
 
 struct alternate_object_database *alloc_alt_odb(const char *dir)
@@ -465,19 +456,19 @@ struct alternate_object_database *alloc_alt_odb(const char *dir)
 
 void add_to_alternates_file(const char *reference)
 {
-       struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+       struct lock_file lock = LOCK_INIT;
        char *alts = git_pathdup("objects/info/alternates");
        FILE *in, *out;
+       int found = 0;
 
-       hold_lock_file_for_update(lock, alts, LOCK_DIE_ON_ERROR);
-       out = fdopen_lock_file(lock, "w");
+       hold_lock_file_for_update(&lock, alts, LOCK_DIE_ON_ERROR);
+       out = fdopen_lock_file(&lock, "w");
        if (!out)
                die_errno("unable to fdopen alternates lockfile");
 
        in = fopen(alts, "r");
        if (in) {
                struct strbuf line = STRBUF_INIT;
-               int found = 0;
 
                while (strbuf_getline(&line, in) != EOF) {
                        if (!strcmp(reference, line.buf)) {
@@ -489,21 +480,18 @@ void add_to_alternates_file(const char *reference)
 
                strbuf_release(&line);
                fclose(in);
-
-               if (found) {
-                       rollback_lock_file(lock);
-                       lock = NULL;
-               }
        }
        else if (errno != ENOENT)
                die_errno("unable to read alternates file");
 
-       if (lock) {
+       if (found) {
+               rollback_lock_file(&lock);
+       } else {
                fprintf_or_die(out, "%s\n", reference);
-               if (commit_lock_file(lock))
+               if (commit_lock_file(&lock))
                        die_errno("unable to move new alternates file into place");
                if (alt_odb_tail)
-                       link_alt_odb_entries(reference, strlen(reference), '\n', NULL, 0);
+                       link_alt_odb_entries(reference, '\n', NULL, 0);
        }
        free(alts);
 }
@@ -516,7 +504,7 @@ void add_to_alternates_memory(const char *reference)
         */
        prepare_alt_odb();
 
-       link_alt_odb_entries(reference, strlen(reference), '\n', NULL, 0);
+       link_alt_odb_entries(reference, '\n', NULL, 0);
 }
 
 /*
@@ -619,7 +607,7 @@ void prepare_alt_odb(void)
        if (!alt) alt = "";
 
        alt_odb_tail = &alt_odb_list;
-       link_alt_odb_entries(alt, strlen(alt), PATH_SEP, NULL, 0);
+       link_alt_odb_entries(alt, PATH_SEP, NULL, 0);
 
        read_info_alternates(get_object_directory(), 0);
 }
@@ -1850,7 +1838,7 @@ int index_path(struct object_id *oid, const char *path, struct stat *st, unsigne
 
 int read_pack_header(int fd, struct pack_header *header)
 {
-       if (read_in_full(fd, header, sizeof(*header)) < sizeof(*header))
+       if (read_in_full(fd, header, sizeof(*header)) != sizeof(*header))
                /* "eof before pack header was fully read" */
                return PH_ERROR_EOF;