git/builtin/shortlog.c
Johannes Schindelin df534dcbaa shortlog: use a stable sort
When sorting the output of `git shortlog` by count, a list of authors in
alphabetical order is then sorted by contribution count. Obviously, the
idea is to maintain the alphabetical order for items with identical
contribution count.

At the moment, this job is performed by `qsort()`. As that function is
not guaranteed to implement a stable sort algorithm, this can lead to
inconsistent and/or surprising behavior: items with identical
contribution count could lose their alphabetical sub-order.

The `qsort()` in MS Visual C's runtime does _not_ implement a stable
sort algorithm, and under certain circumstances this even causes a test
failure in t4201.21 "shortlog can match multiple groups", where two
authors both are listed with 2 contributions, and are listed in inverse
alphabetical order.

Let's instead use the stable sort provided by `git_stable_qsort()` to
avoid this inconsistency.

This is a companion to 2049b8dc65 (diffcore_rename(): use a stable sort,
2019-09-30).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-07-14 11:24:11 -07:00

482 lines
12 KiB
C

#include "builtin.h"
#include "cache.h"
#include "config.h"
#include "commit.h"
#include "diff.h"
#include "string-list.h"
#include "revision.h"
#include "utf8.h"
#include "mailmap.h"
#include "shortlog.h"
#include "parse-options.h"
#include "trailer.h"
#include "strmap.h"
static char const * const shortlog_usage[] = {
N_("git shortlog [<options>] [<revision-range>] [[--] <path>...]"),
N_("git log --pretty=short | git shortlog [<options>]"),
NULL
};
/*
* The util field of our string_list_items will contain one of two things:
*
* - if --summary is not in use, it will point to a string list of the
* oneline subjects assigned to this author
*
* - if --summary is in use, we don't need that list; we only need to know
* its size. So we abuse the pointer slot to store our integer counter.
*
* This macro accesses the latter.
*/
#define UTIL_TO_INT(x) ((intptr_t)(x)->util)
static int compare_by_counter(const void *a1, const void *a2)
{
const struct string_list_item *i1 = a1, *i2 = a2;
return UTIL_TO_INT(i2) - UTIL_TO_INT(i1);
}
static int compare_by_list(const void *a1, const void *a2)
{
const struct string_list_item *i1 = a1, *i2 = a2;
const struct string_list *l1 = i1->util, *l2 = i2->util;
if (l1->nr < l2->nr)
return 1;
else if (l1->nr == l2->nr)
return 0;
else
return -1;
}
static void insert_one_record(struct shortlog *log,
const char *ident,
const char *oneline)
{
struct string_list_item *item;
item = string_list_insert(&log->list, ident);
if (log->summary)
item->util = (void *)(UTIL_TO_INT(item) + 1);
else {
char *buffer;
struct strbuf subject = STRBUF_INIT;
const char *eol;
/* Skip any leading whitespace, including any blank lines. */
while (*oneline && isspace(*oneline))
oneline++;
eol = strchr(oneline, '\n');
if (!eol)
eol = oneline + strlen(oneline);
if (starts_with(oneline, "[PATCH")) {
char *eob = strchr(oneline, ']');
if (eob && (!eol || eob < eol))
oneline = eob + 1;
}
while (*oneline && isspace(*oneline) && *oneline != '\n')
oneline++;
format_subject(&subject, oneline, " ");
buffer = strbuf_detach(&subject, NULL);
if (!item->util) {
item->util = xmalloc(sizeof(struct string_list));
string_list_init_nodup(item->util);
}
string_list_append(item->util, buffer);
}
}
static int parse_ident(struct shortlog *log,
struct strbuf *out, const char *in)
{
const char *mailbuf, *namebuf;
size_t namelen, maillen;
struct ident_split ident;
if (split_ident_line(&ident, in, strlen(in)))
return -1;
namebuf = ident.name_begin;
mailbuf = ident.mail_begin;
namelen = ident.name_end - ident.name_begin;
maillen = ident.mail_end - ident.mail_begin;
map_user(&log->mailmap, &mailbuf, &maillen, &namebuf, &namelen);
strbuf_add(out, namebuf, namelen);
if (log->email)
strbuf_addf(out, " <%.*s>", (int)maillen, mailbuf);
return 0;
}
static void read_from_stdin(struct shortlog *log)
{
struct strbuf ident = STRBUF_INIT;
struct strbuf mapped_ident = STRBUF_INIT;
struct strbuf oneline = STRBUF_INIT;
static const char *author_match[2] = { "Author: ", "author " };
static const char *committer_match[2] = { "Commit: ", "committer " };
const char **match;
if (HAS_MULTI_BITS(log->groups))
die(_("using multiple --group options with stdin is not supported"));
switch (log->groups) {
case SHORTLOG_GROUP_AUTHOR:
match = author_match;
break;
case SHORTLOG_GROUP_COMMITTER:
match = committer_match;
break;
case SHORTLOG_GROUP_TRAILER:
die(_("using --group=trailer with stdin is not supported"));
default:
BUG("unhandled shortlog group");
}
while (strbuf_getline_lf(&ident, stdin) != EOF) {
const char *v;
if (!skip_prefix(ident.buf, match[0], &v) &&
!skip_prefix(ident.buf, match[1], &v))
continue;
while (strbuf_getline_lf(&oneline, stdin) != EOF &&
oneline.len)
; /* discard headers */
while (strbuf_getline_lf(&oneline, stdin) != EOF &&
!oneline.len)
; /* discard blanks */
strbuf_reset(&mapped_ident);
if (parse_ident(log, &mapped_ident, v) < 0)
continue;
insert_one_record(log, mapped_ident.buf, oneline.buf);
}
strbuf_release(&ident);
strbuf_release(&mapped_ident);
strbuf_release(&oneline);
}
static void insert_records_from_trailers(struct shortlog *log,
struct strset *dups,
struct commit *commit,
struct pretty_print_context *ctx,
const char *oneline)
{
struct trailer_iterator iter;
const char *commit_buffer, *body;
struct strbuf ident = STRBUF_INIT;
/*
* Using format_commit_message("%B") would be simpler here, but
* this saves us copying the message.
*/
commit_buffer = logmsg_reencode(commit, NULL, ctx->output_encoding);
body = strstr(commit_buffer, "\n\n");
if (!body)
return;
trailer_iterator_init(&iter, body);
while (trailer_iterator_advance(&iter)) {
const char *value = iter.val.buf;
if (!string_list_has_string(&log->trailers, iter.key.buf))
continue;
strbuf_reset(&ident);
if (!parse_ident(log, &ident, value))
value = ident.buf;
if (!strset_add(dups, value))
continue;
insert_one_record(log, value, oneline);
}
trailer_iterator_release(&iter);
strbuf_release(&ident);
unuse_commit_buffer(commit, commit_buffer);
}
void shortlog_add_commit(struct shortlog *log, struct commit *commit)
{
struct strbuf ident = STRBUF_INIT;
struct strbuf oneline = STRBUF_INIT;
struct strset dups = STRSET_INIT;
struct pretty_print_context ctx = {0};
const char *oneline_str;
ctx.fmt = CMIT_FMT_USERFORMAT;
ctx.abbrev = log->abbrev;
ctx.print_email_subject = 1;
ctx.date_mode.type = DATE_NORMAL;
ctx.output_encoding = get_log_output_encoding();
if (!log->summary) {
if (log->user_format)
pretty_print_commit(&ctx, commit, &oneline);
else
format_commit_message(commit, "%s", &oneline, &ctx);
}
oneline_str = oneline.len ? oneline.buf : "<none>";
if (log->groups & SHORTLOG_GROUP_AUTHOR) {
strbuf_reset(&ident);
format_commit_message(commit,
log->email ? "%aN <%aE>" : "%aN",
&ident, &ctx);
if (!HAS_MULTI_BITS(log->groups) ||
strset_add(&dups, ident.buf))
insert_one_record(log, ident.buf, oneline_str);
}
if (log->groups & SHORTLOG_GROUP_COMMITTER) {
strbuf_reset(&ident);
format_commit_message(commit,
log->email ? "%cN <%cE>" : "%cN",
&ident, &ctx);
if (!HAS_MULTI_BITS(log->groups) ||
strset_add(&dups, ident.buf))
insert_one_record(log, ident.buf, oneline_str);
}
if (log->groups & SHORTLOG_GROUP_TRAILER) {
insert_records_from_trailers(log, &dups, commit, &ctx, oneline_str);
}
strset_clear(&dups);
strbuf_release(&ident);
strbuf_release(&oneline);
}
static void get_from_rev(struct rev_info *rev, struct shortlog *log)
{
struct commit *commit;
if (prepare_revision_walk(rev))
die(_("revision walk setup failed"));
while ((commit = get_revision(rev)) != NULL)
shortlog_add_commit(log, commit);
}
static int parse_uint(char const **arg, int comma, int defval)
{
unsigned long ul;
int ret;
char *endp;
ul = strtoul(*arg, &endp, 10);
if (*endp && *endp != comma)
return -1;
if (ul > INT_MAX)
return -1;
ret = *arg == endp ? defval : (int)ul;
*arg = *endp ? endp + 1 : endp;
return ret;
}
static const char wrap_arg_usage[] = "-w[<width>[,<indent1>[,<indent2>]]]";
#define DEFAULT_WRAPLEN 76
#define DEFAULT_INDENT1 6
#define DEFAULT_INDENT2 9
static int parse_wrap_args(const struct option *opt, const char *arg, int unset)
{
struct shortlog *log = opt->value;
log->wrap_lines = !unset;
if (unset)
return 0;
if (!arg) {
log->wrap = DEFAULT_WRAPLEN;
log->in1 = DEFAULT_INDENT1;
log->in2 = DEFAULT_INDENT2;
return 0;
}
log->wrap = parse_uint(&arg, ',', DEFAULT_WRAPLEN);
log->in1 = parse_uint(&arg, ',', DEFAULT_INDENT1);
log->in2 = parse_uint(&arg, '\0', DEFAULT_INDENT2);
if (log->wrap < 0 || log->in1 < 0 || log->in2 < 0)
return error(wrap_arg_usage);
if (log->wrap &&
((log->in1 && log->wrap <= log->in1) ||
(log->in2 && log->wrap <= log->in2)))
return error(wrap_arg_usage);
return 0;
}
static int parse_group_option(const struct option *opt, const char *arg, int unset)
{
struct shortlog *log = opt->value;
const char *field;
if (unset) {
log->groups = 0;
string_list_clear(&log->trailers, 0);
} else if (!strcasecmp(arg, "author"))
log->groups |= SHORTLOG_GROUP_AUTHOR;
else if (!strcasecmp(arg, "committer"))
log->groups |= SHORTLOG_GROUP_COMMITTER;
else if (skip_prefix(arg, "trailer:", &field)) {
log->groups |= SHORTLOG_GROUP_TRAILER;
string_list_append(&log->trailers, field);
} else
return error(_("unknown group type: %s"), arg);
return 0;
}
void shortlog_init(struct shortlog *log)
{
memset(log, 0, sizeof(*log));
read_mailmap(&log->mailmap);
log->list.strdup_strings = 1;
log->wrap = DEFAULT_WRAPLEN;
log->in1 = DEFAULT_INDENT1;
log->in2 = DEFAULT_INDENT2;
log->trailers.strdup_strings = 1;
log->trailers.cmp = strcasecmp;
}
int cmd_shortlog(int argc, const char **argv, const char *prefix)
{
struct shortlog log = { STRING_LIST_INIT_NODUP };
struct rev_info rev;
int nongit = !startup_info->have_repository;
const struct option options[] = {
OPT_BIT('c', "committer", &log.groups,
N_("group by committer rather than author"),
SHORTLOG_GROUP_COMMITTER),
OPT_BOOL('n', "numbered", &log.sort_by_number,
N_("sort output according to the number of commits per author")),
OPT_BOOL('s', "summary", &log.summary,
N_("suppress commit descriptions, only provides commit count")),
OPT_BOOL('e', "email", &log.email,
N_("show the email address of each author")),
OPT_CALLBACK_F('w', NULL, &log, N_("<w>[,<i1>[,<i2>]]"),
N_("linewrap output"), PARSE_OPT_OPTARG,
&parse_wrap_args),
OPT_CALLBACK(0, "group", &log, N_("field"),
N_("group by field"), parse_group_option),
OPT_END(),
};
struct parse_opt_ctx_t ctx;
git_config(git_default_config, NULL);
shortlog_init(&log);
repo_init_revisions(the_repository, &rev, prefix);
parse_options_start(&ctx, argc, argv, prefix, options,
PARSE_OPT_KEEP_DASHDASH | PARSE_OPT_KEEP_ARGV0);
for (;;) {
switch (parse_options_step(&ctx, options, shortlog_usage)) {
case PARSE_OPT_NON_OPTION:
case PARSE_OPT_UNKNOWN:
break;
case PARSE_OPT_HELP:
case PARSE_OPT_ERROR:
exit(129);
case PARSE_OPT_COMPLETE:
exit(0);
case PARSE_OPT_DONE:
goto parse_done;
}
parse_revision_opt(&rev, &ctx, options, shortlog_usage);
}
parse_done:
revision_opts_finish(&rev);
argc = parse_options_end(&ctx);
if (nongit && argc > 1) {
error(_("too many arguments given outside repository"));
usage_with_options(shortlog_usage, options);
}
if (setup_revisions(argc, argv, &rev, NULL) != 1) {
error(_("unrecognized argument: %s"), argv[1]);
usage_with_options(shortlog_usage, options);
}
log.user_format = rev.commit_format == CMIT_FMT_USERFORMAT;
log.abbrev = rev.abbrev;
log.file = rev.diffopt.file;
if (!log.groups)
log.groups = SHORTLOG_GROUP_AUTHOR;
string_list_sort(&log.trailers);
/* assume HEAD if from a tty */
if (!nongit && !rev.pending.nr && isatty(0))
add_head_to_pending(&rev);
if (rev.pending.nr == 0) {
if (isatty(0))
fprintf(stderr, _("(reading log message from standard input)\n"));
read_from_stdin(&log);
}
else
get_from_rev(&rev, &log);
release_revisions(&rev);
shortlog_output(&log);
if (log.file != stdout)
fclose(log.file);
return 0;
}
static void add_wrapped_shortlog_msg(struct strbuf *sb, const char *s,
const struct shortlog *log)
{
strbuf_add_wrapped_text(sb, s, log->in1, log->in2, log->wrap);
strbuf_addch(sb, '\n');
}
void shortlog_output(struct shortlog *log)
{
size_t i, j;
struct strbuf sb = STRBUF_INIT;
if (log->sort_by_number)
STABLE_QSORT(log->list.items, log->list.nr,
log->summary ? compare_by_counter : compare_by_list);
for (i = 0; i < log->list.nr; i++) {
const struct string_list_item *item = &log->list.items[i];
if (log->summary) {
fprintf(log->file, "%6d\t%s\n",
(int)UTIL_TO_INT(item), item->string);
} else {
struct string_list *onelines = item->util;
fprintf(log->file, "%s (%"PRIuMAX"):\n",
item->string, (uintmax_t)onelines->nr);
for (j = onelines->nr; j >= 1; j--) {
const char *msg = onelines->items[j - 1].string;
if (log->wrap_lines) {
strbuf_reset(&sb);
add_wrapped_shortlog_msg(&sb, msg, log);
fwrite(sb.buf, sb.len, 1, log->file);
}
else
fprintf(log->file, " %s\n", msg);
}
putc('\n', log->file);
onelines->strdup_strings = 1;
string_list_clear(onelines, 0);
free(onelines);
}
log->list.items[i].util = NULL;
}
strbuf_release(&sb);
log->list.strdup_strings = 1;
string_list_clear(&log->list, 1);
clear_mailmap(&log->mailmap);
}