date.c: allow even more varied time formats

[git.git] / sha1_file.c

diff --git a/sha1_file.c b/sha1_file.c
index 28ad159..29f48d5 100644 (file)
--- a/sha1_file.c
+++ b/sha1_file.c
@@ -73,7 +73,7 @@ char *sha1_file_name(const unsigned char *sha1)
        if (!base) {
                char *sha1_file_directory = getenv(DB_ENVIRONMENT) ? : DEFAULT_DB_ENVIRONMENT;
                int len = strlen(sha1_file_directory);
-               base = malloc(len + 60);
+               base = xmalloc(len + 60);
                memcpy(base, sha1_file_directory, len);
                memset(base+len, 0, 60);
                base[len] = '/';
@@ -155,15 +155,13 @@ void * unpack_sha1_file(void *map, unsigned long mapsize, char *type, unsigned l
 
        inflateInit(&stream);
        ret = inflate(&stream, 0);
-       if (ret < Z_OK)
-               return NULL;
+       if (ret < Z_OK)
+               return NULL;
        if (sscanf(buffer, "%10s %lu", type, size) != 2)
                return NULL;
 
        bytes = strlen(buffer) + 1;
-       buf = malloc(*size);
-       if (!buf)
-               return NULL;
+       buf = xmalloc(*size);
 
        memcpy(buf, buffer + bytes, stream.total_out - bytes);
        bytes = stream.total_out - bytes;
@@ -191,47 +189,52 @@ void * read_sha1_file(const unsigned char *sha1, char *type, unsigned long *size
        return NULL;
 }
 
-void *read_tree_with_tree_or_commit_sha1(const unsigned char *sha1,
-                                        unsigned long *size,
-                                        unsigned char *tree_sha1_return)
+void *read_object_with_reference(const unsigned char *sha1,
+                                const unsigned char *required_type,
+                                unsigned long *size,
+                                unsigned char *actual_sha1_return)
 {
        char type[20];
        void *buffer;
        unsigned long isize;
-       int was_commit = 0;
-       unsigned char tree_sha1[20];
-
-       buffer = read_sha1_file(sha1, type, &isize);
-
-       /* 
-        * We might have read a commit instead of a tree, in which case
-        * we parse out the tree_sha1 and attempt to read from there.
-        * (buffer + 5) is because the tree sha1 is always at offset 5
-        * in a commit record ("tree ").
-        */
-       if (buffer &&
-           !strcmp(type, "commit") &&
-           !get_sha1_hex(buffer + 5, tree_sha1)) {
-               free(buffer);
-               buffer = read_sha1_file(tree_sha1, type, &isize);
-               was_commit = 1;
-       }
+       unsigned char actual_sha1[20];
 
-       /*
-        * Now do we have something and if so is it a tree?
-        */
-       if (!buffer || strcmp(type, "tree")) {
-               free(buffer);
-               return NULL;
-       }
+       memcpy(actual_sha1, sha1, 20);
+       while (1) {
+               int ref_length = -1;
+               const char *ref_type = NULL;
 
-       *size = isize;
-       if (tree_sha1_return)
-               memcpy(tree_sha1_return, was_commit ? tree_sha1 : sha1, 20);
-       return buffer;
+               buffer = read_sha1_file(actual_sha1, type, &isize);
+               if (!buffer)
+                       return NULL;
+               if (!strcmp(type, required_type)) {
+                       *size = isize;
+                       if (actual_sha1_return)
+                               memcpy(actual_sha1_return, actual_sha1, 20);
+                       return buffer;
+               }
+               /* Handle references */
+               else if (!strcmp(type, "commit"))
+                       ref_type = "tree ";
+               else if (!strcmp(type, "tag"))
+                       ref_type = "object ";
+               else {
+                       free(buffer);
+                       return NULL;
+               }
+               ref_length = strlen(ref_type);
+
+               if (memcmp(buffer, ref_type, ref_length) ||
+                   get_sha1_hex(buffer + ref_length, actual_sha1)) {
+                       free(buffer);
+                       return NULL;
+               }
+               /* Now we have the ID of the referred-to object in
+                * actual_sha1.  Check again. */
+       }
 }
 
-int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
+int write_sha1_file(char *buf, unsigned long len, const char *type, unsigned char *returnsha1)
 {
        int size;
        char *compressed;
@@ -239,10 +242,15 @@ int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
        unsigned char sha1[20];
        SHA_CTX c;
        char *filename;
-       int fd;
+       char hdr[50];
+       int fd, hdrlen;
+
+       /* 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);
 
@@ -265,14 +273,22 @@ int write_sha1_file(char *buf, unsigned len, unsigned char *returnsha1)
        /* Set it up */
        memset(&stream, 0, sizeof(stream));
        deflateInit(&stream, Z_BEST_COMPRESSION);
-       size = deflateBound(&stream, len);
-       compressed = malloc(size);
+       size = deflateBound(&stream, len+hdrlen);
+       compressed = xmalloc(size);
 
        /* Compress it */
-       stream.next_in = buf;
-       stream.avail_in = len;
        stream.next_out = compressed;
        stream.avail_out = size;
+
+       /* First header.. */
+       stream.next_in = hdr;
+       stream.avail_in = hdrlen;
+       while (deflate(&stream, 0) == Z_OK)
+               /* nothing */
+
+       /* Then the data itself.. */
+       stream.next_in = buf;
+       stream.avail_in = len;
        while (deflate(&stream, Z_FINISH) == Z_OK)
                /* nothing */;
        deflateEnd(&stream);