[PATCH] Diff-tree-helper take two.
[gitweb.git] / diff-tree-helper.c
index 293e00b702a14f6d2ace7dd88e176b6291f12510..bcf89a57892ac3601ac268b08c7f28d443c75108 100644 (file)
@@ -1,3 +1,6 @@
+/*
+ * Copyright (C) 2005 Junio C Hamano
+ */
 #include "cache.h"
 #include "strbuf.h"
 #include "diff.h"
@@ -17,15 +20,22 @@ static int matches_pathspec(const char *name, char **spec, int cnt)
        return 0;
 }
 
-static int parse_oneside_change(const char *cp, unsigned char *sha1,
-                               char *path) {
+static int parse_oneside_change(const char *cp, struct diff_spec *one,
+                               char *path)
+{
        int ch;
-       while ((ch = *cp) && '0' <= ch && ch <= '7')
-               cp++; /* skip mode bits */
+
+       one->file_valid = one->sha1_valid = 1;
+       one->mode = 0;
+       while ((ch = *cp) && '0' <= ch && ch <= '7') {
+               one->mode = (one->mode << 3) | (ch - '0');
+               cp++;
+       }
+
        if (strncmp(cp, "\tblob\t", 6))
                return -1;
        cp += 6;
-       if (get_sha1_hex(cp, sha1))
+       if (get_sha1_hex(cp, one->u.sha1))
                return -1;
        cp += 40;
        if (*cp++ != '\t')
@@ -34,31 +44,20 @@ static int parse_oneside_change(const char *cp, unsigned char *sha1,
        return 0;
 }
 
-#define STATUS_CACHED    0 /* cached and sha1 valid */
-#define STATUS_ABSENT    1 /* diff-tree says old removed or new added */
-#define STATUS_UNCACHED  2 /* diff-cache output: read from working tree */
-
 static int parse_diff_tree_output(const char *buf,
-                                 unsigned char *old_sha1,
-                                 int *old_status,
-                                 unsigned char *new_sha1,
-                                 int *new_status,
+                                 struct diff_spec *old,
+                                 struct diff_spec *new,
                                  char *path) {
        const char *cp = buf;
        int ch;
-       static unsigned char null_sha[20] = { 0, };
 
        switch (*cp++) {
        case '+':
-               *old_status = STATUS_ABSENT;
-               *new_status = (memcmp(new_sha1, null_sha, sizeof(null_sha)) ?
-                              STATUS_CACHED : STATUS_UNCACHED);
-               return parse_oneside_change(cp, new_sha1, path);
+               old->file_valid = 0;
+               return parse_oneside_change(cp, new, path);
        case '-':
-               *new_status = STATUS_ABSENT;
-               *old_status = (memcmp(old_sha1, null_sha, sizeof(null_sha)) ?
-                              STATUS_CACHED : STATUS_UNCACHED);
-               return parse_oneside_change(cp, old_sha1, path);
+               new->file_valid = 0;
+               return parse_oneside_change(cp, old, path);
        case '*':
                break;
        default:
@@ -66,191 +65,36 @@ static int parse_diff_tree_output(const char *buf,
        }
        
        /* This is for '*' entries */
-       while ((ch = *cp) && ('0' <= ch && ch <= '7'))
-               cp++; /* skip mode bits */
+       old->file_valid = old->sha1_valid = 1;
+       new->file_valid = new->sha1_valid = 1;
+
+       old->mode = new->mode = 0;
+       while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
+               old->mode = (old->mode << 3) | (ch - '0');
+               cp++;
+       }
        if (strncmp(cp, "->", 2))
                return -1;
        cp += 2;
-       while ((ch = *cp) && ('0' <= ch && ch <= '7'))
-               cp++; /* skip mode bits */
+       while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
+               new->mode = (new->mode << 3) | (ch - '0');
+               cp++;
+       }
        if (strncmp(cp, "\tblob\t", 6))
                return -1;
        cp += 6;
-       if (get_sha1_hex(cp, old_sha1))
+       if (get_sha1_hex(cp, old->u.sha1))
                return -1;
        cp += 40;
        if (strncmp(cp, "->", 2))
                return -1;
        cp += 2;
-       if (get_sha1_hex(cp, new_sha1))
+       if (get_sha1_hex(cp, new->u.sha1))
                return -1;
        cp += 40;
        if (*cp++ != '\t')
                return -1;
        strcpy(path, cp);
-       *old_status = (memcmp(old_sha1, null_sha, sizeof(null_sha)) ?
-                      STATUS_CACHED : STATUS_UNCACHED);
-       *new_status = (memcmp(new_sha1, null_sha, sizeof(null_sha)) ?
-                      STATUS_CACHED : STATUS_UNCACHED);
-       return 0;
-}
-
-static int sha1err(const char *path, const unsigned char *sha1)
-{
-       return error("diff-tree-helper: unable to read sha1 file of %s (%s)",
-                    path, sha1_to_hex(sha1));
-}
-
-static int fserr(const char *path)
-{
-       return error("diff-tree-helper: unable to read file %s", path);
-}
-
-static char *map_whole_file(const char *path, unsigned long *size) {
-       int fd;
-       struct stat st;
-       void *buf;
-
-       if ((fd = open(path, O_RDONLY)) < 0) {
-               error("diff-tree-helper: unable to read file %s", path);
-               return 0;
-       }
-       if (fstat(fd, &st) < 0) {
-               close(fd);
-               error("diff-tree-helper: unable to stat file %s", path);
-               return 0;
-       }
-       *size = st.st_size;
-       buf = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
-       close(fd);
-       return buf;
-}
-
-static int show_diff(const unsigned char *old_sha1, int old_status,
-                    const unsigned char *new_sha1, int new_status,
-                    const char *path, int reverse_diff)
-{
-       char other[PATH_MAX];
-       unsigned long size;
-       char type[20];
-       int fd;
-       int reverse;
-       void *blob = 0;
-       const char *fs = 0;
-       int need_unmap = 0;
-       int need_unlink = 0;
-
-
-       switch (old_status) {
-       case STATUS_CACHED:
-               blob = read_sha1_file(old_sha1, type, &size);
-               if (! blob)
-                       return sha1err(path, old_sha1);
-                       
-               switch (new_status) {
-               case STATUS_CACHED:
-                       strcpy(other, ".diff_tree_helper_XXXXXX");
-                       fd = mkstemp(other);
-                       if (fd < 0)
-                               die("unable to create temp-file");
-                       if (write(fd, blob, size) != size)
-                               die("unable to write temp-file");
-                       close(fd);
-                       free(blob);
-
-                       blob = read_sha1_file(new_sha1, type, &size);
-                       if (! blob)
-                               return sha1err(path, new_sha1);
-
-                       need_unlink = 1;
-                       /* new = blob, old = fs */
-                       reverse = !reverse_diff;
-                       fs = other;
-                       break;
-
-               case STATUS_ABSENT:
-               case STATUS_UNCACHED:
-                       fs = ((new_status == STATUS_ABSENT) ?
-                             "/dev/null" : path);
-                       reverse = reverse_diff;
-                       break;
-
-               default:
-                       reverse = reverse_diff;
-               }
-               break;
-
-       case STATUS_ABSENT:
-               switch (new_status) {
-               case STATUS_CACHED:
-                       blob = read_sha1_file(new_sha1, type, &size);
-                       if (! blob)
-                               return sha1err(path, new_sha1);
-                       /* old = fs, new = blob */
-                       fs = "/dev/null";
-                       reverse = !reverse_diff;
-                       break;
-
-               case STATUS_ABSENT:
-                       return error("diff-tree-helper: absent from both old and new?");
-               case STATUS_UNCACHED:
-                       fs = path;
-                       blob = strdup("");
-                       size = 0;
-                       /* old = blob, new = fs */
-                       reverse = reverse_diff;
-                       break;
-               default:
-                       reverse = reverse_diff;
-               }
-               break;
-
-       case STATUS_UNCACHED:
-               fs = path; /* old = fs, new = blob */
-               reverse = !reverse_diff;
-
-               switch (new_status) {
-               case STATUS_CACHED:
-                       blob = read_sha1_file(new_sha1, type, &size);
-                       if (! blob)
-                               return sha1err(path, new_sha1);
-                       break;
-
-               case STATUS_ABSENT:
-                       blob = strdup("");
-                       size = 0;
-                       break;
-
-               case STATUS_UNCACHED:
-                       /* old = fs */
-                       blob = map_whole_file(path, &size);
-                       if (! blob)
-                               return fserr(path);
-                       need_unmap = 1;
-                       break;
-               default:
-                       reverse = reverse_diff;
-               }
-               break;
-
-       default:
-               reverse = reverse_diff;
-       }
-       
-       if (fs)
-               show_differences(fs,
-                                path, /* label */
-                                blob,
-                                size,
-                                reverse /* 0: diff blob fs
-                                           1: diff fs blob */);
-
-       if (need_unlink)
-               unlink(other);
-       if (need_unmap && blob)
-               munmap(blob, size);
-       else
-               free(blob);
        return 0;
 }
 
@@ -275,28 +119,20 @@ int main(int ac, char **av) {
        }
        /* the remaining parameters are paths patterns */
 
-       prepare_diff_cmd();
-
        while (1) {
-               int old_status, new_status;
-               unsigned char old_sha1[20], new_sha1[20];
+               struct diff_spec old, new;
                char path[PATH_MAX];
                read_line(&sb, stdin, line_termination);
                if (sb.eof)
                        break;
-               if (parse_diff_tree_output(sb.buf,
-                                          old_sha1, &old_status,
-                                          new_sha1, &new_status,
-                                          path)) {
+               if (parse_diff_tree_output(sb.buf, &old, &new, path)) { 
                        fprintf(stderr, "cannot parse %s\n", sb.buf);
                        continue;
                }
-               if (1 < ac && ! matches_pathspec(path, av+1, ac-1))
+               if (1 < ac && !matches_pathspec(path, av+1, ac-1))
                        continue;
 
-               show_diff(old_sha1, old_status,
-                         new_sha1, new_status,
-                         path, reverse_diff);
+               run_external_diff(path, &old, &new);
        }
        return 0;
 }