Guard a test against wc that pads its output with whitespace
[gitweb.git] / apply.c
diff --git a/apply.c b/apply.c
index a002e156c7663786d41ad88f59d9bea3d027bd2e..d5e7bfdb4de1fe7990ae11e190537fd1c490d54c 100644 (file)
--- a/apply.c
+++ b/apply.c
 //  --numstat does numeric diffstat, and doesn't actually apply
 //  --index-info shows the old and new index info for paths if available.
 //
+static const char *prefix;
+static int prefix_length = -1;
+
+static int allow_binary_replacement = 0;
 static int check_index = 0;
 static int write_index = 0;
 static int diffstat = 0;
@@ -27,7 +31,7 @@ static int no_add = 0;
 static int show_index_info = 0;
 static int line_termination = '\n';
 static const char apply_usage[] =
-"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [-z] <patch>...";
+"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] <patch>...";
 
 /*
  * For "diff-stat" like behaviour, we keep track of the biggest change
@@ -80,14 +84,11 @@ static void *read_patch_file(int fd, unsigned long *sizep)
                        buffer = xrealloc(buffer, alloc);
                        nr = alloc - size;
                }
-               nr = read(fd, buffer + size, nr);
+               nr = xread(fd, buffer + size, nr);
                if (!nr)
                        break;
-               if (nr < 0) {
-                       if (errno == EAGAIN)
-                               continue;
+               if (nr < 0)
                        die("git-apply: read returned %s", strerror(errno));
-               }
                size += nr;
        }
        *sizep = size;
@@ -892,19 +893,33 @@ static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
        patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
 
        if (!patchsize) {
-               static const char binhdr[] = "Binary files ";
-
-               if (sizeof(binhdr) - 1 < size - offset - hdrsize &&
-                   !memcmp(binhdr, buffer + hdrsize + offset,
-                           sizeof(binhdr)-1))
-                       patch->is_binary = 1;
+               static const char *binhdr[] = {
+                       "Binary files ",
+                       "Files ",
+                       NULL,
+               };
+               int i;
+               int hd = hdrsize + offset;
+               unsigned long llen = linelen(buffer + hd, size - hd);
+
+               if (!memcmp(" differ\n", buffer + hd + llen - 8, 8))
+                       for (i = 0; binhdr[i]; i++) {
+                               int len = strlen(binhdr[i]);
+                               if (len < size - hd &&
+                                   !memcmp(binhdr[i], buffer + hd, len)) {
+                                       patch->is_binary = 1;
+                                       break;
+                               }
+                       }
 
                /* Empty patch cannot be applied if:
-                * - it is a binary patch or
-                * - metadata does not change and is not a binary patch.
+                * - it is a binary patch and we do not do binary_replace, or
+                * - text patch without metadata change
                 */
                if ((apply || check) &&
-                   (patch->is_binary || !metadata_changes(patch)))
+                   (patch->is_binary
+                    ? !allow_binary_replacement
+                    : !metadata_changes(patch)))
                        die("patch with only garbage at line %d", linenr);
        }
 
@@ -988,13 +1003,8 @@ static int read_old_data(struct stat *st, const char *path, void *buf, unsigned
                        return error("unable to open %s", path);
                got = 0;
                for (;;) {
-                       int ret = read(fd, buf + got, size - got);
-                       if (ret < 0) {
-                               if (errno == EAGAIN)
-                                       continue;
-                               break;
-                       }
-                       if (!ret)
+                       int ret = xread(fd, buf + got, size - got);
+                       if (ret <= 0)
                                break;
                        got += ret;
                }
@@ -1158,10 +1168,77 @@ static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
 static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
 {
        struct fragment *frag = patch->fragments;
+       const char *name = patch->old_name ? patch->old_name : patch->new_name;
+
+       if (patch->is_binary) {
+               unsigned char sha1[20];
+
+               if (!allow_binary_replacement)
+                       return error("cannot apply binary patch to '%s' "
+                                    "without --allow-binary-replacement",
+                                    name);
+
+               /* For safety, we require patch index line to contain
+                * full 40-byte textual SHA1 for old and new, at least for now.
+                */
+               if (strlen(patch->old_sha1_prefix) != 40 ||
+                   strlen(patch->new_sha1_prefix) != 40 ||
+                   get_sha1_hex(patch->old_sha1_prefix, sha1) ||
+                   get_sha1_hex(patch->new_sha1_prefix, sha1))
+                       return error("cannot apply binary patch to '%s' "
+                                    "without full index line", name);
+
+               if (patch->old_name) {
+                       unsigned char hdr[50];
+                       int hdrlen;
+
+                       /* See if the old one matches what the patch
+                        * applies to.
+                        */
+                       write_sha1_file_prepare(desc->buffer, desc->size,
+                                               "blob", sha1, hdr, &hdrlen);
+                       if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
+                               return error("the patch applies to '%s' (%s), "
+                                            "which does not match the "
+                                            "current contents.",
+                                            name, sha1_to_hex(sha1));
+               }
+               else {
+                       /* Otherwise, the old one must be empty. */
+                       if (desc->size)
+                               return error("the patch applies to an empty "
+                                            "'%s' but it is not empty", name);
+               }
+
+               /* For now, we do not record post-image data in the patch,
+                * and require the object already present in the recipient's
+                * object database.
+                */
+               if (desc->buffer) {
+                       free(desc->buffer);
+                       desc->alloc = desc->size = 0;
+               }
+               get_sha1_hex(patch->new_sha1_prefix, sha1);
+
+               if (memcmp(sha1, null_sha1, 20)) {
+                       char type[10];
+                       unsigned long size;
+
+                       desc->buffer = read_sha1_file(sha1, type, &size);
+                       if (!desc->buffer)
+                               return error("the necessary postimage %s for "
+                                            "'%s' does not exist",
+                                            patch->new_sha1_prefix, name);
+                       desc->alloc = desc->size = size;
+               }
+
+               return 0;
+       }
 
        while (frag) {
                if (apply_one_fragment(desc, frag) < 0)
-                       return error("patch failed: %s:%ld", patch->old_name, frag->oldpos);
+                       return error("patch failed: %s:%ld",
+                                    name, frag->oldpos);
                frag = frag->next;
        }
        return 0;
@@ -1203,6 +1280,7 @@ static int check_patch(struct patch *patch)
        struct stat st;
        const char *old_name = patch->old_name;
        const char *new_name = patch->new_name;
+       const char *name = old_name ? old_name : new_name;
 
        if (old_name) {
                int changed;
@@ -1277,7 +1355,7 @@ static int check_patch(struct patch *patch)
        }       
 
        if (apply_data(patch, &st) < 0)
-               return error("%s: patch does not apply", old_name);
+               return error("%s: patch does not apply", name);
        return 0;
 }
 
@@ -1514,12 +1592,9 @@ static int try_create_file(const char *path, unsigned int mode, const char *buf,
        if (fd < 0)
                return -1;
        while (size) {
-               int written = write(fd, buf, size);
-               if (written < 0) {
-                       if (errno == EINTR || errno == EAGAIN)
-                               continue;
+               int written = xwrite(fd, buf, size);
+               if (written < 0)
                        die("writing file %s: %s", path, strerror(errno));
-               }
                if (!written)
                        die("out of space writing file %s", path);
                buf += written;
@@ -1623,6 +1698,12 @@ static int use_patch(struct patch *p)
                        return 0;
                x = x->next;
        }
+       if (0 < prefix_length) {
+               int pathlen = strlen(pathname);
+               if (pathlen <= prefix_length ||
+                   memcmp(prefix, pathname, prefix_length))
+                       return 0;
+       }
        return 1;
 }
 
@@ -1726,6 +1807,10 @@ int main(int argc, char **argv)
                        diffstat = 1;
                        continue;
                }
+               if (!strcmp(arg, "--allow-binary-replacement")) {
+                       allow_binary_replacement = 1;
+                       continue;
+               }
                if (!strcmp(arg, "--numstat")) {
                        apply = 0;
                        numstat = 1;
@@ -1758,6 +1843,15 @@ int main(int argc, char **argv)
                        line_termination = 0;
                        continue;
                }
+
+               if (check_index && prefix_length < 0) {
+                       prefix = setup_git_directory();
+                       prefix_length = prefix ? strlen(prefix) : 0;
+                       git_config(git_default_config);
+               }
+               if (0 < prefix_length)
+                       arg = prefix_filename(prefix, prefix_length, arg);
+
                fd = open(arg, O_RDONLY);
                if (fd < 0)
                        usage(apply_usage);