blame: use built-in xdiff

This removes the last use of external diff from core git suite.
Also addresses the use of index() -- elsewhere we tend to use
strchr().

Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/blame.c b/blame.c
index 98f9992..1ee0d32 100644 (file)
--- a/blame.c
+++ b/blame.c
@@ -16,6 +16,7 @@
 #include "diff.h"
 #include "diffcore.h"
 #include "revision.h"
+#include "xdiff-interface.h"
 
 #define DEBUG 0
 
@@ -57,116 +58,89 @@ static int num_get_patch = 0;
 static int num_commits = 0;
 static int patch_time = 0;
 
-#define TEMPFILE_PATH_LEN 60
-static struct patch *get_patch(struct commit *commit, struct commit *other)
-{
+struct blame_diff_state {
+       struct xdiff_emit_state xm;
        struct patch *ret;
-       struct util_info *info_c = (struct util_info *)commit->object.util;
-       struct util_info *info_o = (struct util_info *)other->object.util;
-       char tmp_path1[TEMPFILE_PATH_LEN], tmp_path2[TEMPFILE_PATH_LEN];
-       char diff_cmd[TEMPFILE_PATH_LEN*2 + 20];
-       struct timeval tv_start, tv_end;
-       int fd;
-       FILE *fin;
-       char buf[1024];
-
-       ret = xmalloc(sizeof(struct patch));
-       ret->chunks = NULL;
-       ret->num = 0;
-
-       get_blob(commit);
-       get_blob(other);
+};
 
-       gettimeofday(&tv_start, NULL);
+static void process_u0_diff(void *state_, char *line, unsigned long len)
+{
+       struct blame_diff_state *state = state_;
+       struct chunk *chunk;
 
-       fd = git_mkstemp(tmp_path1, TEMPFILE_PATH_LEN, "git-blame-XXXXXX");
-       if (fd < 0)
-               die("unable to create temp-file: %s", strerror(errno));
+       if (len < 4 || line[0] != '@' || line[1] != '@')
+               return;
 
-       if (xwrite(fd, info_c->buf, info_c->size) != info_c->size)
-               die("write failed: %s", strerror(errno));
-       close(fd);
+       if (DEBUG)
+               printf("chunk line: %.*s", (int)len, line);
+       state->ret->num++;
+       state->ret->chunks = xrealloc(state->ret->chunks,
+                                     sizeof(struct chunk) * state->ret->num);
+       chunk = &state->ret->chunks[state->ret->num - 1];
+
+       assert(!strncmp(line, "@@ -", 4));
+
+       if (parse_hunk_header(line, len,
+                             &chunk->off1, &chunk->len1,
+                             &chunk->off2, &chunk->len2)) {
+               state->ret->num--;
+               return;
+       }
 
-       fd = git_mkstemp(tmp_path2, TEMPFILE_PATH_LEN, "git-blame-XXXXXX");
-       if (fd < 0)
-               die("unable to create temp-file: %s", strerror(errno));
+       if (chunk->len1 == 0)
+               chunk->off1++;
+       if (chunk->len2 == 0)
+               chunk->off2++;
 
-       if (xwrite(fd, info_o->buf, info_o->size) != info_o->size)
-               die("write failed: %s", strerror(errno));
-       close(fd);
+       if (chunk->off1 > 0)
+               chunk->off1--;
+       if (chunk->off2 > 0)
+               chunk->off2--;
 
-       sprintf(diff_cmd, "diff -U 0 %s %s", tmp_path1, tmp_path2);
-       fin = popen(diff_cmd, "r");
-       if (!fin)
-               die("popen failed: %s", strerror(errno));
+       assert(chunk->off1 >= 0);
+       assert(chunk->off2 >= 0);
+}
 
-       while (fgets(buf, sizeof(buf), fin)) {
-               struct chunk *chunk;
-               char *start, *sp;
+static struct patch *get_patch(struct commit *commit, struct commit *other)
+{
+       struct blame_diff_state state;
+       xpparam_t xpp;
+       xdemitconf_t xecfg;
+       mmfile_t file_c, file_o;
+       xdemitcb_t ecb;
+       struct util_info *info_c = (struct util_info *)commit->object.util;
+       struct util_info *info_o = (struct util_info *)other->object.util;
+       struct timeval tv_start, tv_end;
 
-               if (buf[0] != '@' || buf[1] != '@')
-                       continue;
+       get_blob(commit);
+       file_c.ptr = info_c->buf;
+       file_c.size = info_c->size;
 
-               if (DEBUG)
-                       printf("chunk line: %s", buf);
-               ret->num++;
-               ret->chunks = xrealloc(ret->chunks,
-                                      sizeof(struct chunk) * ret->num);
-               chunk = &ret->chunks[ret->num - 1];
-
-               assert(!strncmp(buf, "@@ -", 4));
-
-               start = buf + 4;
-               sp = index(start, ' ');
-               *sp = '\0';
-               if (index(start, ',')) {
-                       int ret =
-                           sscanf(start, "%d,%d", &chunk->off1, &chunk->len1);
-                       assert(ret == 2);
-               } else {
-                       int ret = sscanf(start, "%d", &chunk->off1);
-                       assert(ret == 1);
-                       chunk->len1 = 1;
-               }
-               *sp = ' ';
-
-               start = sp + 1;
-               sp = index(start, ' ');
-               *sp = '\0';
-               if (index(start, ',')) {
-                       int ret =
-                           sscanf(start, "%d,%d", &chunk->off2, &chunk->len2);
-                       assert(ret == 2);
-               } else {
-                       int ret = sscanf(start, "%d", &chunk->off2);
-                       assert(ret == 1);
-                       chunk->len2 = 1;
-               }
-               *sp = ' ';
+       get_blob(other);
+       file_o.ptr = info_o->buf;
+       file_o.size = info_o->size;
 
-               if (chunk->len1 == 0)
-                       chunk->off1++;
-               if (chunk->len2 == 0)
-                       chunk->off2++;
+       gettimeofday(&tv_start, NULL);
 
-               if (chunk->off1 > 0)
-                       chunk->off1--;
-               if (chunk->off2 > 0)
-                       chunk->off2--;
+       xpp.flags = XDF_NEED_MINIMAL;
+       xecfg.ctxlen = 0;
+       xecfg.flags = 0;
+       ecb.outf = xdiff_outf;
+       ecb.priv = &state;
+       memset(&state, 0, sizeof(state));
+       state.xm.consume = process_u0_diff;
+       state.ret = xmalloc(sizeof(struct patch));
+       state.ret->chunks = NULL;
+       state.ret->num = 0;
 
-               assert(chunk->off1 >= 0);
-               assert(chunk->off2 >= 0);
-       }
-       pclose(fin);
-       unlink(tmp_path1);
-       unlink(tmp_path2);
+       xdl_diff(&file_c, &file_o, &xpp, &xecfg, &ecb);
 
        gettimeofday(&tv_end, NULL);
        patch_time += 1000000 * (tv_end.tv_sec - tv_start.tv_sec) +
                tv_end.tv_usec - tv_start.tv_usec;
 
        num_get_patch++;
-       return ret;
+       return state.ret;
 }
 
 static void free_patch(struct patch *p)
@@ -674,7 +648,7 @@ static void get_commit_info(struct commit* commit, struct commit_info* ret)
        static char author_buf[1024];
 
        tmp = strstr(commit->buffer, "\nauthor ") + 8;
-       len = index(tmp, '\n') - tmp;
+       len = strchr(tmp, '\n') - tmp;
        ret->author = author_buf;
        memcpy(ret->author, tmp, len);
 
@@ -875,7 +849,7 @@ int main(int argc, const char **argv)
                        if(blame_contents[blame_len-1] != '\n')
                                putc('\n', stdout);
                } else {
-                       char* next_buf = index(buf, '\n') + 1;
+                       char* next_buf = strchr(buf, '\n') + 1;
                        fwrite(buf, next_buf - buf, 1, stdout);
                        buf = next_buf;
                }