merge-recursive: don't segfault while handling rename clashes

diff --git a/builtin-merge.c b/builtin-merge.c
index 5e2b7f12c35ab1bfebda66f7ee9180c68e7f23c4..2179e0686dda496fb6ec83bd03fc7135f2e6e040 100644 (file)
--- a/builtin-merge.c
+++ b/builtin-merge.c
@@ -50,6 +50,7 @@ static unsigned char head[20], stash[20];
 static struct strategy **use_strategies;
 static size_t use_strategies_nr, use_strategies_alloc;
 static const char *branch;
+static int verbosity;
 
 static struct strategy all_strategy[] = {
        { "recursive",  DEFAULT_TWOHEAD | NO_TRIVIAL },
@@ -171,6 +172,7 @@ static struct option builtin_merge_options[] = {
        OPT_CALLBACK('m', "message", &merge_msg, "message",
                "message to be used for the merge commit (if any)",
                option_parse_message),
+       OPT__VERBOSITY(&verbosity),
        OPT_END()
 };
 
@@ -179,6 +181,7 @@ static void drop_save(void)
 {
        unlink(git_path("MERGE_HEAD"));
        unlink(git_path("MERGE_MSG"));
+       unlink(git_path("MERGE_MODE"));
 }
 
 static void save_state(void)
@@ -249,7 +252,8 @@ static void restore_state(void)
 /* This is called when no merge was necessary. */
 static void finish_up_to_date(const char *msg)
 {
-       printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
+       if (verbosity >= 0)
+               printf("%s%s\n", squash ? " (nothing to squash)" : "", msg);
        drop_save();
 }
 
@@ -289,8 +293,10 @@ static void squash_message(void)
                pretty_print_commit(rev.commit_format, commit, &out, rev.abbrev,
                        NULL, NULL, rev.date_mode, 0);
        }
-       write(fd, out.buf, out.len);
-       close(fd);
+       if (write(fd, out.buf, out.len) < 0)
+               die("Writing SQUASH_MSG: %s", strerror(errno));
+       if (close(fd))
+               die("Finishing SQUASH_MSG: %s", strerror(errno));
        strbuf_release(&out);
 }
 
@@ -330,14 +336,15 @@ static void finish(const unsigned char *new_head, const char *msg)
        if (!msg)
                strbuf_addstr(&reflog_message, getenv("GIT_REFLOG_ACTION"));
        else {
-               printf("%s\n", msg);
+               if (verbosity >= 0)
+                       printf("%s\n", msg);
                strbuf_addf(&reflog_message, "%s: %s",
                        getenv("GIT_REFLOG_ACTION"), msg);
        }
        if (squash) {
                squash_message();
        } else {
-               if (!merge_msg.len)
+               if (verbosity >= 0 && !merge_msg.len)
                        printf("No merge message -- not updating HEAD\n");
                else {
                        const char *argv_gc_auto[] = { "gc", "--auto", NULL };
@@ -778,7 +785,7 @@ static int suggest_conflicts(void)
 
        fp = fopen(git_path("MERGE_MSG"), "a");
        if (!fp)
-               die("Could open %s for writing", git_path("MERGE_MSG"));
+               die("Could not open %s for writing", git_path("MERGE_MSG"));
        fprintf(fp, "\nConflicts:\n");
        for (pos = 0; pos < active_nr; pos++) {
                struct cache_entry *ce = active_cache[pos];
@@ -871,6 +878,8 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
        argc = parse_options(argc, argv, builtin_merge_options,
                        builtin_merge_usage, 0);
+       if (verbosity < 0)
+               show_diffstat = 0;
 
        if (squash) {
                if (!allow_fast_forward)
@@ -1012,10 +1021,11 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
 
                strcpy(hex, find_unique_abbrev(head, DEFAULT_ABBREV));
 
-               printf("Updating %s..%s\n",
-                       hex,
-                       find_unique_abbrev(remoteheads->item->object.sha1,
-                       DEFAULT_ABBREV));
+               if (verbosity >= 0)
+                       printf("Updating %s..%s\n",
+                               hex,
+                               find_unique_abbrev(remoteheads->item->object.sha1,
+                               DEFAULT_ABBREV));
                strbuf_addstr(&msg, "Fast forward");
                if (have_message)
                        strbuf_addstr(&msg,
@@ -1210,6 +1220,15 @@ int cmd_merge(int argc, const char **argv, const char *prefix)
                        merge_msg.len)
                        die("Could not write to %s", git_path("MERGE_MSG"));
                close(fd);
+               fd = open(git_path("MERGE_MODE"), O_WRONLY | O_CREAT | O_TRUNC, 0666);
+               if (fd < 0)
+                       die("Could open %s for writing", git_path("MERGE_MODE"));
+               strbuf_reset(&buf);
+               if (!allow_fast_forward)
+                       strbuf_addf(&buf, "no-ff");
+               if (write_in_full(fd, buf.buf, buf.len) != buf.len)
+                       die("Could not write to %s", git_path("MERGE_MODE"));
+               close(fd);
        }
 
        if (merge_was_ok) {