Axe the last ent
[gitweb.git] / builtin-tar-tree.c
index e97e0af985515df14b37a6f0e5cc84b2c943f8c6..aeb5a8c2ad886f60bc402eb56a1bd2e37698ab7d 100644 (file)
 #define BLOCKSIZE      (RECORDSIZE * 20)
 
 static const char tar_tree_usage[] =
-"git-tar-tree [--remote=<repo>] <ent> [basedir]";
+"git-tar-tree [--remote=<repo>] <tree-ish> [basedir]";
 
 static char block[BLOCKSIZE];
 static unsigned long offset;
 
 static time_t archive_time;
+static int tar_umask;
 
 /* tries hard to write, either succeeds or dies in the attempt */
-static void reliable_write(void *buf, unsigned long size)
+static void reliable_write(const void *data, unsigned long size)
 {
+       const char *buf = data;
+
        while (size > 0) {
                long ret = xwrite(1, buf, size);
                if (ret < 0) {
@@ -47,37 +50,13 @@ static void write_if_needed(void)
        }
 }
 
-/* acquire the next record from the buffer; user must call write_if_needed() */
-static char *get_record(void)
-{
-       char *p = block + offset;
-       memset(p, 0, RECORDSIZE);
-       offset += RECORDSIZE;
-       return p;
-}
-
-/*
- * The end of tar archives is marked by 1024 nul bytes and after that
- * follows the rest of the block (if any).
- */
-static void write_trailer(void)
-{
-       get_record();
-       write_if_needed();
-       get_record();
-       write_if_needed();
-       while (offset) {
-               get_record();
-               write_if_needed();
-       }
-}
-
 /*
  * queues up writes, so that all our write(2) calls write exactly one
  * full block; pads writes to RECORDSIZE
  */
-static void write_blocked(void *buf, unsigned long size)
+static void write_blocked(const void *data, unsigned long size)
 {
+       const char *buf = data;
        unsigned long tail;
 
        if (offset) {
@@ -107,6 +86,21 @@ static void write_blocked(void *buf, unsigned long size)
        write_if_needed();
 }
 
+/*
+ * The end of tar archives is marked by 2*512 nul bytes and after that
+ * follows the rest of the block (if any).
+ */
+static void write_trailer(void)
+{
+       int tail = BLOCKSIZE - offset;
+       memset(block + offset, 0, tail);
+       reliable_write(block, BLOCKSIZE);
+       if (tail < 2 * RECORDSIZE) {
+               memset(block, 0, offset);
+               reliable_write(block, BLOCKSIZE);
+       }
+}
+
 static void strbuf_append_string(struct strbuf *sb, const char *s)
 {
        int slen = strlen(s);
@@ -168,8 +162,9 @@ static int get_path_prefix(const struct strbuf *path, int maxlen)
        int i = path->len;
        if (i > maxlen)
                i = maxlen;
-       while (i > 0 && path->buf[i] != '/')
+       do {
                i--;
+       } while (i > 0 && path->buf[i] != '/');
        return i;
 }
 
@@ -194,13 +189,13 @@ static void write_entry(const unsigned char *sha1, struct strbuf *path,
        } else {
                if (S_ISDIR(mode)) {
                        *header.typeflag = TYPEFLAG_DIR;
-                       mode |= 0777;
+                       mode = (mode | 0777) & ~tar_umask;
                } else if (S_ISLNK(mode)) {
                        *header.typeflag = TYPEFLAG_LNK;
                        mode |= 0777;
                } else if (S_ISREG(mode)) {
                        *header.typeflag = TYPEFLAG_REG;
-                       mode |= (mode & 0100) ? 0777 : 0666;
+                       mode = (mode | ((mode & 0100) ? 0777 : 0666)) & ~tar_umask;
                } else {
                        error("unsupported file mode: 0%o (SHA1: %s)",
                              mode, sha1_to_hex(sha1));
@@ -239,8 +234,8 @@ static void write_entry(const unsigned char *sha1, struct strbuf *path,
        /* XXX: should we provide more meaningful info here? */
        sprintf(header.uid, "%07o", 0);
        sprintf(header.gid, "%07o", 0);
-       strncpy(header.uname, "git", 31);
-       strncpy(header.gname, "git", 31);
+       strlcpy(header.uname, "git", sizeof(header.uname));
+       strlcpy(header.gname, "git", sizeof(header.gname));
        sprintf(header.devmajor, "%07o", 0);
        sprintf(header.devminor, "%07o", 0);
 
@@ -271,30 +266,25 @@ static void write_global_extended_header(const unsigned char *sha1)
 static void traverse_tree(struct tree_desc *tree, struct strbuf *path)
 {
        int pathlen = path->len;
+       struct name_entry entry;
 
-       while (tree->size) {
-               const char *name;
-               const unsigned char *sha1;
-               unsigned mode;
+       while (tree_entry(tree, &entry)) {
                void *eltbuf;
                char elttype[20];
                unsigned long eltsize;
 
-               sha1 = tree_entry_extract(tree, &name, &mode);
-               update_tree_entry(tree);
-
-               eltbuf = read_sha1_file(sha1, elttype, &eltsize);
+               eltbuf = read_sha1_file(entry.sha1, elttype, &eltsize);
                if (!eltbuf)
-                       die("cannot read %s", sha1_to_hex(sha1));
+                       die("cannot read %s", sha1_to_hex(entry.sha1));
 
                path->len = pathlen;
-               strbuf_append_string(path, name);
-               if (S_ISDIR(mode))
+               strbuf_append_string(path, entry.path);
+               if (S_ISDIR(entry.mode))
                        strbuf_append_string(path, "/");
 
-               write_entry(sha1, path, mode, eltbuf, eltsize);
+               write_entry(entry.sha1, path, entry.mode, eltbuf, eltsize);
 
-               if (S_ISDIR(mode)) {
+               if (S_ISDIR(entry.mode)) {
                        struct tree_desc subtree;
                        subtree.buf = eltbuf;
                        subtree.size = eltsize;
@@ -304,19 +294,33 @@ static void traverse_tree(struct tree_desc *tree, struct strbuf *path)
        }
 }
 
-int generate_tar(int argc, const char **argv)
+int git_tar_config(const char *var, const char *value)
+{
+       if (!strcmp(var, "tar.umask")) {
+               if (!strcmp(value, "user")) {
+                       tar_umask = umask(0);
+                       umask(tar_umask);
+               } else {
+                       tar_umask = git_config_int(var, value);
+               }
+               return 0;
+       }
+       return git_default_config(var, value);
+}
+
+static int generate_tar(int argc, const char **argv, const char *prefix)
 {
        unsigned char sha1[20], tree_sha1[20];
        struct commit *commit;
        struct tree_desc tree;
        struct strbuf current_path;
+       void *buffer;
 
        current_path.buf = xmalloc(PATH_MAX);
        current_path.alloc = PATH_MAX;
        current_path.len = current_path.eof = 0;
 
-       setup_git_directory();
-       git_config(git_default_config);
+       git_config(git_tar_config);
 
        switch (argc) {
        case 3:
@@ -338,8 +342,8 @@ int generate_tar(int argc, const char **argv)
        } else
                archive_time = time(NULL);
 
-       tree.buf = read_object_with_reference(sha1, tree_type, &tree.size,
-                                             tree_sha1);
+       tree.buf = buffer = read_object_with_reference(sha1, tree_type,
+                                                      &tree.size, tree_sha1);
        if (!tree.buf)
                die("not a reference to a tag, commit or tree object: %s",
                    sha1_to_hex(sha1));
@@ -348,6 +352,7 @@ int generate_tar(int argc, const char **argv)
                write_entry(tree_sha1, &current_path, 040777, NULL, 0);
        traverse_tree(&tree, &current_path);
        write_trailer();
+       free(buffer);
        free(current_path.buf);
        return 0;
 }
@@ -398,11 +403,36 @@ static int remote_tar(int argc, const char **argv)
        return !!ret;
 }
 
-int cmd_tar_tree(int argc, const char **argv, char **envp)
+int cmd_tar_tree(int argc, const char **argv, const char *prefix)
 {
        if (argc < 2)
                usage(tar_tree_usage);
        if (!strncmp("--remote=", argv[1], 9))
                return remote_tar(argc, argv);
-       return generate_tar(argc, argv);
+       return generate_tar(argc, argv, prefix);
+}
+
+/* ustar header + extended global header content */
+#define HEADERSIZE (2 * RECORDSIZE)
+
+int cmd_get_tar_commit_id(int argc, const char **argv, const char *prefix)
+{
+       char buffer[HEADERSIZE];
+       struct ustar_header *header = (struct ustar_header *)buffer;
+       char *content = buffer + RECORDSIZE;
+       ssize_t n;
+
+       n = xread(0, buffer, HEADERSIZE);
+       if (n < HEADERSIZE)
+               die("git-get-tar-commit-id: read error");
+       if (header->typeflag[0] != 'g')
+               return 1;
+       if (memcmp(content, "52 comment=", 11))
+               return 1;
+
+       n = xwrite(1, content + 11, 41);
+       if (n < 41)
+               die("git-get-tar-commit-id: write error");
+
+       return 0;
 }