[PATCH] Consolidate the error handling

[git.git] / read-tree.c

diff --git a/read-tree.c b/read-tree.c
index 3785e25..9aec97f 100644 (file)
--- a/read-tree.c
+++ b/read-tree.c
@@ -5,33 +5,23 @@
  */
 #include "cache.h"
 
-static void create_directories(const char *path)
+static int read_one_entry(unsigned char *sha1, const char *base, int baselen, const char *pathname, unsigned mode)
 {
-       int len = strlen(path);
-       char *buf = malloc(len + 1);
-       const char *slash = path;
+       int len = strlen(pathname);
+       unsigned int size = cache_entry_size(baselen + len);
+       struct cache_entry *ce = malloc(size);
 
-       while ((slash = strchr(slash+1, '/')) != NULL) {
-               len = slash - path;
-               memcpy(buf, path, len);
-               buf[len] = 0;
-               mkdir(buf, 0700);
-       }
-}
+       memset(ce, 0, size);
 
-static int create_file(const char *path)
-{
-       int fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0600);
-       if (fd < 0) {
-               if (errno == ENOENT) {
-                       create_directories(path);
-                       fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0600);
-               }
-       }
-       return fd;
+       ce->st_mode = mode;
+       ce->namelen = baselen + len;
+       memcpy(ce->name, base, baselen);
+       memcpy(ce->name + baselen, pathname, len+1);
+       memcpy(ce->sha1, sha1, 20);
+       return add_cache_entry(ce, 1);
 }
 
-static int unpack(unsigned char *sha1)
+static int read_tree(unsigned char *sha1, const char *base, int baselen)
 {
        void *buffer;
        unsigned long size;
@@ -39,50 +29,78 @@ static int unpack(unsigned char *sha1)
 
        buffer = read_sha1_file(sha1, type, &size);
        if (!buffer)
-               usage("unable to read sha1 file");
+               return -1;
        if (strcmp(type, "tree"))
-               usage("expected a 'tree' node");
+               return -1;
        while (size) {
                int len = strlen(buffer)+1;
                unsigned char *sha1 = buffer + len;
                char *path = strchr(buffer, ' ')+1;
-               char *data;
-               unsigned long filesize;
                unsigned int mode;
-               int fd;
 
                if (size < len + 20 || sscanf(buffer, "%o", &mode) != 1)
-                       usage("corrupt 'tree' file");
+                       return -1;
+
                buffer = sha1 + 20;
                size -= len + 20;
-               data = read_sha1_file(sha1, type, &filesize);
-               if (!data || strcmp(type, "blob"))
-                       usage("tree file refers to bad file data");
-               fd = create_file(path);
-               if (fd < 0)
-                       usage("unable to create file");
-               if (write(fd, data, filesize) != filesize)
-                       usage("unable to write file");
-               fchmod(fd, mode);
-               close(fd);
-               free(data);
+
+               if (S_ISDIR(mode)) {
+                       int retval;
+                       int pathlen = strlen(path);
+                       char *newbase = malloc(baselen + 1 + pathlen);
+                       memcpy(newbase, base, baselen);
+                       memcpy(newbase + baselen, path, pathlen);
+                       newbase[baselen + pathlen] = '/';
+                       retval = read_tree(sha1, newbase, baselen + pathlen + 1);
+                       free(newbase);
+                       if (retval)
+                               return -1;
+                       continue;
+               }
+               if (read_one_entry(sha1, base, baselen, path, mode) < 0)
+                       return -1;
        }
        return 0;
 }
 
+static int remove_lock = 0;
+
+static void remove_lock_file(void)
+{
+       if (remove_lock)
+               unlink(".git/index.lock");
+}
+
 int main(int argc, char **argv)
 {
-       int fd;
+       int i, newfd;
        unsigned char sha1[20];
 
-       if (argc != 2)
-               usage("read-tree <key>");
-       if (get_sha1_hex(argv[1], sha1) < 0)
-               usage("read-tree <key>");
-       sha1_file_directory = getenv(DB_ENVIRONMENT);
-       if (!sha1_file_directory)
-               sha1_file_directory = DEFAULT_DB_ENVIRONMENT;
-       if (unpack(sha1) < 0)
-               usage("unpack failed");
+       newfd = open(".git/index.lock", O_RDWR | O_CREAT | O_EXCL, 0600);
+       if (newfd < 0)
+               die("unable to create new cachefile");
+       atexit(remove_lock_file);
+       remove_lock = 1;
+
+       for (i = 1; i < argc; i++) {
+               const char *arg = argv[i];
+
+               /* "-m" stands for "merge" current directory cache */
+               if (!strcmp(arg, "-m")) {
+                       if (active_cache)
+                               die("read-tree: cannot merge old cache on top of new");
+                       if (read_cache() < 0)
+                               die("read-tree: corrupt directory cache");
+                       continue;
+               }
+               if (get_sha1_hex(arg, sha1) < 0)
+                       usage("read-tree [-m] <sha1>");
+               if (read_tree(sha1, "", 0) < 0)
+                       die("failed to unpack tree object %s", arg);
+       }
+       if (write_cache(newfd, active_cache, active_nr) ||
+           rename(".git/index.lock", ".git/index"))
+               die("unable to write new index file");
+       remove_lock = 0;
        return 0;
 }