format-patch: pass a commit to reopen_stdout()

We use the commit to generate the patch filename in reopen_stdout()
before we redirect stdout. The cover letter codepath creates a dummy
commit with the desired subject line 'cover letter'.

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin-log.c b/builtin-log.c
index 193de3ff2e4a0dd82f3ba05dc05cb30995718152..6a27ce6958e119f55e39848f1156deb3e801f80f 100644 (file)
--- a/builtin-log.c
+++ b/builtin-log.c
@@ -539,30 +539,29 @@ static FILE *realstdout = NULL;
 static const char *output_directory = NULL;
 static int outdir_offset;
 
-static int reopen_stdout(const char *oneline, struct rev_info *rev)
+static int reopen_stdout(struct commit *commit, struct rev_info *rev)
 {
-       char filename[PATH_MAX];
-       int len = 0;
+       struct strbuf filename = STRBUF_INIT;
        int suffix_len = strlen(fmt_patch_suffix) + 1;
 
        if (output_directory) {
-               len = snprintf(filename, sizeof(filename), "%s",
-                               output_directory);
-               if (len >=
-                   sizeof(filename) - FORMAT_PATCH_NAME_MAX - suffix_len)
+               strbuf_addstr(&filename, output_directory);
+               if (filename.len >=
+                   PATH_MAX - FORMAT_PATCH_NAME_MAX - suffix_len)
                        return error("name of output directory is too long");
-               if (filename[len - 1] != '/')
-                       filename[len++] = '/';
+               if (filename.buf[filename.len - 1] != '/')
+                       strbuf_addch(&filename, '/');
        }
 
-       strncpy(filename + len, oneline, PATH_MAX - len);
+       get_patch_filename(commit, rev->nr, fmt_patch_suffix, &filename);
 
        if (!DIFF_OPT_TST(&rev->diffopt, QUIET))
-               fprintf(realstdout, "%s\n", filename + outdir_offset);
+               fprintf(realstdout, "%s\n", filename.buf + outdir_offset);
 
-       if (freopen(filename, "w", stdout) == NULL)
-               return error("Cannot open patch file %s",filename);
+       if (freopen(filename.buf, "w", stdout) == NULL)
+               return error("Cannot open patch file %s", filename.buf);
 
+       strbuf_release(&filename);
        return 0;
 }
 
@@ -643,26 +642,42 @@ static void make_cover_letter(struct rev_info *rev, int use_stdout,
        const char *encoding = "utf-8";
        struct diff_options opts;
        int need_8bit_cte = 0;
-       char filename[PATH_MAX];
+       struct commit *commit = NULL;
 
        if (rev->commit_format != CMIT_FMT_EMAIL)
                die("Cover letter needs email format");
 
-       if (numbered_files)
-               sprintf(filename, "0");
-       else
-               sprintf(filename, "%04d-cover-letter%s", 0, fmt_patch_suffix);
+       committer = git_committer_info(0);
+       head_sha1 = sha1_to_hex(head->object.sha1);
 
-       if (!use_stdout && reopen_stdout(filename, rev))
+       if (!numbered_files) {
+               /*
+                * We fake a commit for the cover letter so we get the filename
+                * desired.
+                */
+               commit = xcalloc(1, sizeof(*commit));
+               commit->buffer = xmalloc(400);
+               snprintf(commit->buffer, 400,
+                       "tree 0000000000000000000000000000000000000000\n"
+                       "parent %s\n"
+                       "author %s\n"
+                       "committer %s\n\n"
+                       "cover letter\n",
+                       head_sha1, committer, committer);
+       }
+
+       if (!use_stdout && reopen_stdout(commit, rev))
                return;
 
-       head_sha1 = sha1_to_hex(head->object.sha1);
+       if (commit) {
+
+               free(commit->buffer);
+               free(commit);
+       }
 
        log_write_email_headers(rev, head_sha1, &subject_start, &extra_headers,
                                &need_8bit_cte);
 
-       committer = git_committer_info(0);
-
        msg = body;
        pp_user_info(NULL, CMIT_FMT_EMAIL, &sb, committer, DATE_RFC2822,
                     encoding);
@@ -766,7 +781,6 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
        struct patch_ids ids;
        char *add_signoff = NULL;
        struct strbuf buf = STRBUF_INIT;
-       struct strbuf patch_filename = STRBUF_INIT;
 
        git_config(git_format_config, NULL);
        init_revisions(&rev, prefix);
@@ -1070,11 +1084,9 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                        gen_message_id(&rev, sha1_to_hex(commit->object.sha1));
                }
 
-               get_patch_filename(numbered_files ? NULL : commit, rev.nr,
-                                   fmt_patch_suffix, &patch_filename);
-               if (!use_stdout && reopen_stdout(patch_filename.buf, &rev))
+               if (!use_stdout && reopen_stdout(numbered_files ? NULL : commit,
+                                                &rev))
                        die("Failed to create output files");
-               strbuf_setlen(&patch_filename, 0);
                shown = log_tree_commit(&rev, commit);
                free(commit->buffer);
                commit->buffer = NULL;
@@ -1098,7 +1110,6 @@ int cmd_format_patch(int argc, const char **argv, const char *prefix)
                if (!use_stdout)
                        fclose(stdout);
        }
-       strbuf_release(&patch_filename);
        free(list);
        if (ignore_if_in_upstream)
                free_patch_ids(&ids);