Allow zero-sized files to be checked in.

The kernel may not want it, but others probably do.

Noted (again) by Junio Hamano.

diff --git a/update-cache.c b/update-cache.c
index 25db789..d08e895 100644 (file)
--- a/update-cache.c
+++ b/update-cache.c
@@ -17,12 +17,16 @@ static int allow_add = 0, allow_remove = 0;
 static int index_fd(const char *path, int namelen, struct cache_entry *ce, int fd, struct stat *st)
 {
        z_stream stream;
-       int max_out_bytes = namelen + st->st_size + 200;
+       unsigned long size = st->st_size;
+       int max_out_bytes = namelen + size + 200;
        void *out = malloc(max_out_bytes);
        void *metadata = malloc(namelen + 200);
-       void *in = mmap(NULL, st->st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+       void *in;
        SHA_CTX c;
 
+       in = "";
+       if (size)
+               in = mmap(NULL, size, PROT_READ, MAP_PRIVATE, fd, 0);
        close(fd);
        if (!out || (int)(long)in == -1)
                return -1;
@@ -34,7 +38,7 @@ static int index_fd(const char *path, int namelen, struct cache_entry *ce, int f
         * ASCII size + nul byte
         */     
        stream.next_in = metadata;
-       stream.avail_in = 1+sprintf(metadata, "blob %lu", (unsigned long) st->st_size);
+       stream.avail_in = 1+sprintf(metadata, "blob %lu", size);
        stream.next_out = out;
        stream.avail_out = max_out_bytes;
        while (deflate(&stream, 0) == Z_OK)
@@ -44,7 +48,7 @@ static int index_fd(const char *path, int namelen, struct cache_entry *ce, int f
         * File content
         */
        stream.next_in = in;
-       stream.avail_in = st->st_size;
+       stream.avail_in = size;
        while (deflate(&stream, Z_FINISH) == Z_OK)
                /*nothing */;