summaryrefslogtreecommitdiff
path: root/help.c
blob: b8f3a98e4cbe09dd903dfb86653938c1d7604e3d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
#include "cache.h"
#include "config.h"
#include "builtin.h"
#include "exec_cmd.h"
#include "levenshtein.h"
#include "help.h"
#include "common-cmds.h"
#include "string-list.h"
#include "column.h"
#include "version.h"
#include "refs.h"

void add_cmdname(struct cmdnames *cmds, const char *name, int len)
{
	struct cmdname *ent;
	FLEX_ALLOC_MEM(ent, name, name, len);
	ent->len = len;

	ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
	cmds->names[cmds->cnt++] = ent;
}

static void clean_cmdnames(struct cmdnames *cmds)
{
	int i;
	for (i = 0; i < cmds->cnt; ++i)
		free(cmds->names[i]);
	free(cmds->names);
	cmds->cnt = 0;
	cmds->alloc = 0;
}

static int cmdname_compare(const void *a_, const void *b_)
{
	struct cmdname *a = *(struct cmdname **)a_;
	struct cmdname *b = *(struct cmdname **)b_;
	return strcmp(a->name, b->name);
}

static void uniq(struct cmdnames *cmds)
{
	int i, j;

	if (!cmds->cnt)
		return;

	for (i = j = 1; i < cmds->cnt; i++) {
		if (!strcmp(cmds->names[i]->name, cmds->names[j-1]->name))
			free(cmds->names[i]);
		else
			cmds->names[j++] = cmds->names[i];
	}

	cmds->cnt = j;
}

void exclude_cmds(struct cmdnames *cmds, struct cmdnames *excludes)
{
	int ci, cj, ei;
	int cmp;

	ci = cj = ei = 0;
	while (ci < cmds->cnt && ei < excludes->cnt) {
		cmp = strcmp(cmds->names[ci]->name, excludes->names[ei]->name);
		if (cmp < 0)
			cmds->names[cj++] = cmds->names[ci++];
		else if (cmp == 0) {
			ei++;
			free(cmds->names[ci++]);
		} else if (cmp > 0)
			ei++;
	}

	while (ci < cmds->cnt)
		cmds->names[cj++] = cmds->names[ci++];

	cmds->cnt = cj;
}

static void pretty_print_cmdnames(struct cmdnames *cmds, unsigned int colopts)
{
	struct string_list list = STRING_LIST_INIT_NODUP;
	struct column_options copts;
	int i;

	for (i = 0; i < cmds->cnt; i++)
		string_list_append(&list, cmds->names[i]->name);
	/*
	 * always enable column display, we only consult column.*
	 * about layout strategy and stuff
	 */
	colopts = (colopts & ~COL_ENABLE_MASK) | COL_ENABLED;
	memset(&copts, 0, sizeof(copts));
	copts.indent = "  ";
	copts.padding = 2;
	print_columns(&list, colopts, &copts);
	string_list_clear(&list, 0);
}

static int is_executable(const char *name)
{
	struct stat st;

	if (stat(name, &st) || /* stat, not lstat */
	    !S_ISREG(st.st_mode))
		return 0;

#if defined(GIT_WINDOWS_NATIVE)
	/*
	 * On Windows there is no executable bit. The file extension
	 * indicates whether it can be run as an executable, and Git
	 * has special-handling to detect scripts and launch them
	 * through the indicated script interpreter. We test for the
	 * file extension first because virus scanners may make
	 * it quite expensive to open many files.
	 */
	if (ends_with(name, ".exe"))
		return S_IXUSR;

{
	/*
	 * Now that we know it does not have an executable extension,
	 * peek into the file instead.
	 */
	char buf[3] = { 0 };
	int n;
	int fd = open(name, O_RDONLY);
	st.st_mode &= ~S_IXUSR;
	if (fd >= 0) {
		n = read(fd, buf, 2);
		if (n == 2)
			/* look for a she-bang */
			if (!strcmp(buf, "#!"))
				st.st_mode |= S_IXUSR;
		close(fd);
	}
}
#endif
	return st.st_mode & S_IXUSR;
}

static void list_commands_in_dir(struct cmdnames *cmds,
					 const char *path,
					 const char *prefix)
{
	DIR *dir = opendir(path);
	struct dirent *de;
	struct strbuf buf = STRBUF_INIT;
	int len;

	if (!dir)
		return;
	if (!prefix)
		prefix = "git-";

	strbuf_addf(&buf, "%s/", path);
	len = buf.len;

	while ((de = readdir(dir)) != NULL) {
		const char *ent;
		size_t entlen;

		if (!skip_prefix(de->d_name, prefix, &ent))
			continue;

		strbuf_setlen(&buf, len);
		strbuf_addstr(&buf, de->d_name);
		if (!is_executable(buf.buf))
			continue;

		entlen = strlen(ent);
		strip_suffix(ent, ".exe", &entlen);

		add_cmdname(cmds, ent, entlen);
	}
	closedir(dir);
	strbuf_release(&buf);
}

void load_command_list(const char *prefix,
		struct cmdnames *main_cmds,
		struct cmdnames *other_cmds)
{
	const char *env_path = getenv("PATH");
	const char *exec_path = git_exec_path();

	if (exec_path) {
		list_commands_in_dir(main_cmds, exec_path, prefix);
		QSORT(main_cmds->names, main_cmds->cnt, cmdname_compare);
		uniq(main_cmds);
	}

	if (env_path) {
		char *paths, *path, *colon;
		path = paths = xstrdup(env_path);
		while (1) {
			if ((colon = strchr(path, PATH_SEP)))
				*colon = 0;
			if (!exec_path || strcmp(path, exec_path))
				list_commands_in_dir(other_cmds, path, prefix);

			if (!colon)
				break;
			path = colon + 1;
		}
		free(paths);

		QSORT(other_cmds->names, other_cmds->cnt, cmdname_compare);
		uniq(other_cmds);
	}
	exclude_cmds(other_cmds, main_cmds);
}

void list_commands(unsigned int colopts,
		   struct cmdnames *main_cmds, struct cmdnames *other_cmds)
{
	if (main_cmds->cnt) {
		const char *exec_path = git_exec_path();
		printf_ln(_("available git commands in '%s'"), exec_path);
		putchar('\n');
		pretty_print_cmdnames(main_cmds, colopts);
		putchar('\n');
	}

	if (other_cmds->cnt) {
		printf_ln(_("git commands available from elsewhere on your $PATH"));
		putchar('\n');
		pretty_print_cmdnames(other_cmds, colopts);
		putchar('\n');
	}
}

static int cmd_group_cmp(const void *elem1, const void *elem2)
{
	const struct cmdname_help *e1 = elem1;
	const struct cmdname_help *e2 = elem2;

	if (e1->group < e2->group)
		return -1;
	if (e1->group > e2->group)
		return 1;
	return strcmp(e1->name, e2->name);
}

void list_common_cmds_help(void)
{
	int i, longest = 0;
	int current_grp = -1;

	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
		if (longest < strlen(common_cmds[i].name))
			longest = strlen(common_cmds[i].name);
	}

	QSORT(common_cmds, ARRAY_SIZE(common_cmds), cmd_group_cmp);

	puts(_("These are common Git commands used in various situations:"));

	for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
		if (common_cmds[i].group != current_grp) {
			printf("\n%s\n", _(common_cmd_groups[common_cmds[i].group]));
			current_grp = common_cmds[i].group;
		}

		printf("   %s   ", common_cmds[i].name);
		mput_char(' ', longest - strlen(common_cmds[i].name));
		puts(_(common_cmds[i].help));
	}
}

int is_in_cmdlist(struct cmdnames *c, const char *s)
{
	int i;
	for (i = 0; i < c->cnt; i++)
		if (!strcmp(s, c->names[i]->name))
			return 1;
	return 0;
}

static int autocorrect;
static struct cmdnames aliases;

static int git_unknown_cmd_config(const char *var, const char *value, void *cb)
{
	const char *p;

	if (!strcmp(var, "help.autocorrect"))
		autocorrect = git_config_int(var,value);
	/* Also use aliases for command lookup */
	if (skip_prefix(var, "alias.", &p))
		add_cmdname(&aliases, p, strlen(p));

	return git_default_config(var, value, cb);
}

static int levenshtein_compare(const void *p1, const void *p2)
{
	const struct cmdname *const *c1 = p1, *const *c2 = p2;
	const char *s1 = (*c1)->name, *s2 = (*c2)->name;
	int l1 = (*c1)->len;
	int l2 = (*c2)->len;
	return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
}

static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
{
	int i;
	ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);

	for (i = 0; i < old->cnt; i++)
		cmds->names[cmds->cnt++] = old->names[i];
	free(old->names);
	old->cnt = 0;
	old->names = NULL;
}

/* An empirically derived magic number */
#define SIMILARITY_FLOOR 7
#define SIMILAR_ENOUGH(x) ((x) < SIMILARITY_FLOOR)

static const char bad_interpreter_advice[] =
	N_("'%s' appears to be a git command, but we were not\n"
	"able to execute it. Maybe git-%s is broken?");

const char *help_unknown_cmd(const char *cmd)
{
	int i, n, best_similarity = 0;
	struct cmdnames main_cmds, other_cmds;

	memset(&main_cmds, 0, sizeof(main_cmds));
	memset(&other_cmds, 0, sizeof(other_cmds));
	memset(&aliases, 0, sizeof(aliases));

	read_early_config(git_unknown_cmd_config, NULL);

	load_command_list("git-", &main_cmds, &other_cmds);

	add_cmd_list(&main_cmds, &aliases);
	add_cmd_list(&main_cmds, &other_cmds);
	QSORT(main_cmds.names, main_cmds.cnt, cmdname_compare);
	uniq(&main_cmds);

	/* This abuses cmdname->len for levenshtein distance */
	for (i = 0, n = 0; i < main_cmds.cnt; i++) {
		int cmp = 0; /* avoid compiler stupidity */
		const char *candidate = main_cmds.names[i]->name;

		/*
		 * An exact match means we have the command, but
		 * for some reason exec'ing it gave us ENOENT; probably
		 * it's a bad interpreter in the #! line.
		 */
		if (!strcmp(candidate, cmd))
			die(_(bad_interpreter_advice), cmd, cmd);

		/* Does the candidate appear in common_cmds list? */
		while (n < ARRAY_SIZE(common_cmds) &&
		       (cmp = strcmp(common_cmds[n].name, candidate)) < 0)
			n++;
		if ((n < ARRAY_SIZE(common_cmds)) && !cmp) {
			/* Yes, this is one of the common commands */
			n++; /* use the entry from common_cmds[] */
			if (starts_with(candidate, cmd)) {
				/* Give prefix match a very good score */
				main_cmds.names[i]->len = 0;
				continue;
			}
		}

		main_cmds.names[i]->len =
			levenshtein(cmd, candidate, 0, 2, 1, 3) + 1;
	}

	QSORT(main_cmds.names, main_cmds.cnt, levenshtein_compare);

	if (!main_cmds.cnt)
		die(_("Uh oh. Your system reports no Git commands at all."));

	/* skip and count prefix matches */
	for (n = 0; n < main_cmds.cnt && !main_cmds.names[n]->len; n++)
		; /* still counting */

	if (main_cmds.cnt <= n) {
		/* prefix matches with everything? that is too ambiguous */
		best_similarity = SIMILARITY_FLOOR + 1;
	} else {
		/* count all the most similar ones */
		for (best_similarity = main_cmds.names[n++]->len;
		     (n < main_cmds.cnt &&
		      best_similarity == main_cmds.names[n]->len);
		     n++)
			; /* still counting */
	}
	if (autocorrect && n == 1 && SIMILAR_ENOUGH(best_similarity)) {
		const char *assumed = main_cmds.names[0]->name;
		main_cmds.names[0] = NULL;
		clean_cmdnames(&main_cmds);
		fprintf_ln(stderr,
			   _("WARNING: You called a Git command named '%s', "
			     "which does not exist.\n"
			     "Continuing under the assumption that you meant '%s'"),
			cmd, assumed);
		if (autocorrect > 0) {
			fprintf_ln(stderr, _("in %0.1f seconds automatically..."),
				(float)autocorrect/10.0);
			sleep_millisec(autocorrect * 100);
		}
		return assumed;
	}

	fprintf_ln(stderr, _("git: '%s' is not a git command. See 'git --help'."), cmd);

	if (SIMILAR_ENOUGH(best_similarity)) {
		fprintf_ln(stderr,
			   Q_("\nDid you mean this?",
			      "\nDid you mean one of these?",
			   n));

		for (i = 0; i < n; i++)
			fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
	}

	exit(1);
}

int cmd_version(int argc, const char **argv, const char *prefix)
{
	/*
	 * The format of this string should be kept stable for compatibility
	 * with external projects that rely on the output of "git version".
	 */
	printf("git version %s\n", git_version_string);
	while (*++argv) {
		if (!strcmp(*argv, "--build-options")) {
			printf("sizeof-long: %d\n", (int)sizeof(long));
			/* NEEDSWORK: also save and output GIT-BUILD_OPTIONS? */
		}
	}
	return 0;
}

struct similar_ref_cb {
	const char *base_ref;
	struct string_list *similar_refs;
};

static int append_similar_ref(const char *refname, const struct object_id *oid,
			      int flags, void *cb_data)
{
	struct similar_ref_cb *cb = (struct similar_ref_cb *)(cb_data);
	char *branch = strrchr(refname, '/') + 1;
	const char *remote;

	/* A remote branch of the same name is deemed similar */
	if (skip_prefix(refname, "refs/remotes/", &remote) &&
	    !strcmp(branch, cb->base_ref))
		string_list_append(cb->similar_refs, remote);
	return 0;
}

static struct string_list guess_refs(const char *ref)
{
	struct similar_ref_cb ref_cb;
	struct string_list similar_refs = STRING_LIST_INIT_NODUP;

	ref_cb.base_ref = ref;
	ref_cb.similar_refs = &similar_refs;
	for_each_ref(append_similar_ref, &ref_cb);
	return similar_refs;
}

void help_unknown_ref(const char *ref, const char *cmd, const char *error)
{
	int i;
	struct string_list suggested_refs = guess_refs(ref);

	fprintf_ln(stderr, _("%s: %s - %s"), cmd, ref, error);

	if (suggested_refs.nr > 0) {
		fprintf_ln(stderr,
			   Q_("\nDid you mean this?",
			      "\nDid you mean one of these?",
			      suggested_refs.nr));
		for (i = 0; i < suggested_refs.nr; i++)
			fprintf(stderr, "\t%s\n", suggested_refs.items[i].string);
	}

	string_list_clear(&suggested_refs, 0);
	exit(1);
}