trace: avoid unnecessary quoting
[git/git.git] / quote.c
1 #include "cache.h"
2 #include "quote.h"
3 #include "argv-array.h"
4
5 int quote_path_fully = 1;
6
7 static inline int need_bs_quote(char c)
8 {
9 return (c == '\'' || c == '!');
10 }
11
12 /* Help to copy the thing properly quoted for the shell safety.
13 * any single quote is replaced with '\'', any exclamation point
14 * is replaced with '\!', and the whole thing is enclosed in a
15 * single quote pair.
16 *
17 * E.g.
18 * original sq_quote result
19 * name ==> name ==> 'name'
20 * a b ==> a b ==> 'a b'
21 * a'b ==> a'\''b ==> 'a'\''b'
22 * a!b ==> a'\!'b ==> 'a'\!'b'
23 */
24 void sq_quote_buf(struct strbuf *dst, const char *src)
25 {
26 char *to_free = NULL;
27
28 if (dst->buf == src)
29 to_free = strbuf_detach(dst, NULL);
30
31 strbuf_addch(dst, '\'');
32 while (*src) {
33 size_t len = strcspn(src, "'!");
34 strbuf_add(dst, src, len);
35 src += len;
36 while (need_bs_quote(*src)) {
37 strbuf_addstr(dst, "'\\");
38 strbuf_addch(dst, *src++);
39 strbuf_addch(dst, '\'');
40 }
41 }
42 strbuf_addch(dst, '\'');
43 free(to_free);
44 }
45
46 void sq_quote_buf_pretty(struct strbuf *dst, const char *src)
47 {
48 static const char ok_punct[] = "+,-./:=@_^";
49 const char *p;
50
51 for (p = src; *p; p++) {
52 if (!isalpha(*p) && !isdigit(*p) && !strchr(ok_punct, *p)) {
53 sq_quote_buf(dst, src);
54 return;
55 }
56 }
57
58 /* if we get here, we did not need quoting */
59 strbuf_addstr(dst, src);
60 }
61
62 void sq_quotef(struct strbuf *dst, const char *fmt, ...)
63 {
64 struct strbuf src = STRBUF_INIT;
65
66 va_list ap;
67 va_start(ap, fmt);
68 strbuf_vaddf(&src, fmt, ap);
69 va_end(ap);
70
71 sq_quote_buf(dst, src.buf);
72 strbuf_release(&src);
73 }
74
75 void sq_quote_argv(struct strbuf *dst, const char **argv)
76 {
77 int i;
78
79 /* Copy into destination buffer. */
80 strbuf_grow(dst, 255);
81 for (i = 0; argv[i]; ++i) {
82 strbuf_addch(dst, ' ');
83 sq_quote_buf(dst, argv[i]);
84 }
85 }
86
87 void sq_quote_argv_pretty(struct strbuf *dst, const char **argv)
88 {
89 int i;
90
91 for (i = 0; argv[i]; i++) {
92 strbuf_addch(dst, ' ');
93 sq_quote_buf_pretty(dst, argv[i]);
94 }
95 }
96
97 static char *sq_dequote_step(char *arg, char **next)
98 {
99 char *dst = arg;
100 char *src = arg;
101 char c;
102
103 if (*src != '\'')
104 return NULL;
105 for (;;) {
106 c = *++src;
107 if (!c)
108 return NULL;
109 if (c != '\'') {
110 *dst++ = c;
111 continue;
112 }
113 /* We stepped out of sq */
114 switch (*++src) {
115 case '\0':
116 *dst = 0;
117 if (next)
118 *next = NULL;
119 return arg;
120 case '\\':
121 c = *++src;
122 if (need_bs_quote(c) && *++src == '\'') {
123 *dst++ = c;
124 continue;
125 }
126 /* Fallthrough */
127 default:
128 if (!next || !isspace(*src))
129 return NULL;
130 do {
131 c = *++src;
132 } while (isspace(c));
133 *dst = 0;
134 *next = src;
135 return arg;
136 }
137 }
138 }
139
140 char *sq_dequote(char *arg)
141 {
142 return sq_dequote_step(arg, NULL);
143 }
144
145 static int sq_dequote_to_argv_internal(char *arg,
146 const char ***argv, int *nr, int *alloc,
147 struct argv_array *array)
148 {
149 char *next = arg;
150
151 if (!*arg)
152 return 0;
153 do {
154 char *dequoted = sq_dequote_step(next, &next);
155 if (!dequoted)
156 return -1;
157 if (argv) {
158 ALLOC_GROW(*argv, *nr + 1, *alloc);
159 (*argv)[(*nr)++] = dequoted;
160 }
161 if (array)
162 argv_array_push(array, dequoted);
163 } while (next);
164
165 return 0;
166 }
167
168 int sq_dequote_to_argv(char *arg, const char ***argv, int *nr, int *alloc)
169 {
170 return sq_dequote_to_argv_internal(arg, argv, nr, alloc, NULL);
171 }
172
173 int sq_dequote_to_argv_array(char *arg, struct argv_array *array)
174 {
175 return sq_dequote_to_argv_internal(arg, NULL, NULL, NULL, array);
176 }
177
178 /* 1 means: quote as octal
179 * 0 means: quote as octal if (quote_path_fully)
180 * -1 means: never quote
181 * c: quote as "\\c"
182 */
183 #define X8(x) x, x, x, x, x, x, x, x
184 #define X16(x) X8(x), X8(x)
185 static signed char const sq_lookup[256] = {
186 /* 0 1 2 3 4 5 6 7 */
187 /* 0x00 */ 1, 1, 1, 1, 1, 1, 1, 'a',
188 /* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r', 1, 1,
189 /* 0x10 */ X16(1),
190 /* 0x20 */ -1, -1, '"', -1, -1, -1, -1, -1,
191 /* 0x28 */ X16(-1), X16(-1), X16(-1),
192 /* 0x58 */ -1, -1, -1, -1,'\\', -1, -1, -1,
193 /* 0x60 */ X16(-1), X8(-1),
194 /* 0x78 */ -1, -1, -1, -1, -1, -1, -1, 1,
195 /* 0x80 */ /* set to 0 */
196 };
197
198 static inline int sq_must_quote(char c)
199 {
200 return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
201 }
202
203 /* returns the longest prefix not needing a quote up to maxlen if positive.
204 This stops at the first \0 because it's marked as a character needing an
205 escape */
206 static size_t next_quote_pos(const char *s, ssize_t maxlen)
207 {
208 size_t len;
209 if (maxlen < 0) {
210 for (len = 0; !sq_must_quote(s[len]); len++);
211 } else {
212 for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
213 }
214 return len;
215 }
216
217 /*
218 * C-style name quoting.
219 *
220 * (1) if sb and fp are both NULL, inspect the input name and counts the
221 * number of bytes that are needed to hold c_style quoted version of name,
222 * counting the double quotes around it but not terminating NUL, and
223 * returns it.
224 * However, if name does not need c_style quoting, it returns 0.
225 *
226 * (2) if sb or fp are not NULL, it emits the c_style quoted version
227 * of name, enclosed with double quotes if asked and needed only.
228 * Return value is the same as in (1).
229 */
230 static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
231 struct strbuf *sb, FILE *fp, int no_dq)
232 {
233 #undef EMIT
234 #define EMIT(c) \
235 do { \
236 if (sb) strbuf_addch(sb, (c)); \
237 if (fp) fputc((c), fp); \
238 count++; \
239 } while (0)
240 #define EMITBUF(s, l) \
241 do { \
242 if (sb) strbuf_add(sb, (s), (l)); \
243 if (fp) fwrite((s), (l), 1, fp); \
244 count += (l); \
245 } while (0)
246
247 size_t len, count = 0;
248 const char *p = name;
249
250 for (;;) {
251 int ch;
252
253 len = next_quote_pos(p, maxlen);
254 if (len == maxlen || (maxlen < 0 && !p[len]))
255 break;
256
257 if (!no_dq && p == name)
258 EMIT('"');
259
260 EMITBUF(p, len);
261 EMIT('\\');
262 p += len;
263 ch = (unsigned char)*p++;
264 if (maxlen >= 0)
265 maxlen -= len + 1;
266 if (sq_lookup[ch] >= ' ') {
267 EMIT(sq_lookup[ch]);
268 } else {
269 EMIT(((ch >> 6) & 03) + '0');
270 EMIT(((ch >> 3) & 07) + '0');
271 EMIT(((ch >> 0) & 07) + '0');
272 }
273 }
274
275 EMITBUF(p, len);
276 if (p == name) /* no ending quote needed */
277 return 0;
278
279 if (!no_dq)
280 EMIT('"');
281 return count;
282 }
283
284 size_t quote_c_style(const char *name, struct strbuf *sb, FILE *fp, int nodq)
285 {
286 return quote_c_style_counted(name, -1, sb, fp, nodq);
287 }
288
289 void quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path, int nodq)
290 {
291 if (quote_c_style(prefix, NULL, NULL, 0) ||
292 quote_c_style(path, NULL, NULL, 0)) {
293 if (!nodq)
294 strbuf_addch(sb, '"');
295 quote_c_style(prefix, sb, NULL, 1);
296 quote_c_style(path, sb, NULL, 1);
297 if (!nodq)
298 strbuf_addch(sb, '"');
299 } else {
300 strbuf_addstr(sb, prefix);
301 strbuf_addstr(sb, path);
302 }
303 }
304
305 void write_name_quoted(const char *name, FILE *fp, int terminator)
306 {
307 if (terminator) {
308 quote_c_style(name, NULL, fp, 0);
309 } else {
310 fputs(name, fp);
311 }
312 fputc(terminator, fp);
313 }
314
315 void write_name_quoted_relative(const char *name, const char *prefix,
316 FILE *fp, int terminator)
317 {
318 struct strbuf sb = STRBUF_INIT;
319
320 name = relative_path(name, prefix, &sb);
321 write_name_quoted(name, fp, terminator);
322
323 strbuf_release(&sb);
324 }
325
326 /* quote path as relative to the given prefix */
327 char *quote_path_relative(const char *in, const char *prefix,
328 struct strbuf *out)
329 {
330 struct strbuf sb = STRBUF_INIT;
331 const char *rel = relative_path(in, prefix, &sb);
332 strbuf_reset(out);
333 quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
334 strbuf_release(&sb);
335
336 return out->buf;
337 }
338
339 /*
340 * C-style name unquoting.
341 *
342 * Quoted should point at the opening double quote.
343 * + Returns 0 if it was able to unquote the string properly, and appends the
344 * result in the strbuf `sb'.
345 * + Returns -1 in case of error, and doesn't touch the strbuf. Though note
346 * that this function will allocate memory in the strbuf, so calling
347 * strbuf_release is mandatory whichever result unquote_c_style returns.
348 *
349 * Updates endp pointer to point at one past the ending double quote if given.
350 */
351 int unquote_c_style(struct strbuf *sb, const char *quoted, const char **endp)
352 {
353 size_t oldlen = sb->len, len;
354 int ch, ac;
355
356 if (*quoted++ != '"')
357 return -1;
358
359 for (;;) {
360 len = strcspn(quoted, "\"\\");
361 strbuf_add(sb, quoted, len);
362 quoted += len;
363
364 switch (*quoted++) {
365 case '"':
366 if (endp)
367 *endp = quoted;
368 return 0;
369 case '\\':
370 break;
371 default:
372 goto error;
373 }
374
375 switch ((ch = *quoted++)) {
376 case 'a': ch = '\a'; break;
377 case 'b': ch = '\b'; break;
378 case 'f': ch = '\f'; break;
379 case 'n': ch = '\n'; break;
380 case 'r': ch = '\r'; break;
381 case 't': ch = '\t'; break;
382 case 'v': ch = '\v'; break;
383
384 case '\\': case '"':
385 break; /* verbatim */
386
387 /* octal values with first digit over 4 overflow */
388 case '0': case '1': case '2': case '3':
389 ac = ((ch - '0') << 6);
390 if ((ch = *quoted++) < '0' || '7' < ch)
391 goto error;
392 ac |= ((ch - '0') << 3);
393 if ((ch = *quoted++) < '0' || '7' < ch)
394 goto error;
395 ac |= (ch - '0');
396 ch = ac;
397 break;
398 default:
399 goto error;
400 }
401 strbuf_addch(sb, ch);
402 }
403
404 error:
405 strbuf_setlen(sb, oldlen);
406 return -1;
407 }
408
409 /* quoting as a string literal for other languages */
410
411 void perl_quote_buf(struct strbuf *sb, const char *src)
412 {
413 const char sq = '\'';
414 const char bq = '\\';
415 char c;
416
417 strbuf_addch(sb, sq);
418 while ((c = *src++)) {
419 if (c == sq || c == bq)
420 strbuf_addch(sb, bq);
421 strbuf_addch(sb, c);
422 }
423 strbuf_addch(sb, sq);
424 }
425
426 void python_quote_buf(struct strbuf *sb, const char *src)
427 {
428 const char sq = '\'';
429 const char bq = '\\';
430 const char nl = '\n';
431 char c;
432
433 strbuf_addch(sb, sq);
434 while ((c = *src++)) {
435 if (c == nl) {
436 strbuf_addch(sb, bq);
437 strbuf_addch(sb, 'n');
438 continue;
439 }
440 if (c == sq || c == bq)
441 strbuf_addch(sb, bq);
442 strbuf_addch(sb, c);
443 }
444 strbuf_addch(sb, sq);
445 }
446
447 void tcl_quote_buf(struct strbuf *sb, const char *src)
448 {
449 char c;
450
451 strbuf_addch(sb, '"');
452 while ((c = *src++)) {
453 switch (c) {
454 case '[': case ']':
455 case '{': case '}':
456 case '$': case '\\': case '"':
457 strbuf_addch(sb, '\\');
458 /* fallthrough */
459 default:
460 strbuf_addch(sb, c);
461 break;
462 case '\f':
463 strbuf_addstr(sb, "\\f");
464 break;
465 case '\r':
466 strbuf_addstr(sb, "\\r");
467 break;
468 case '\n':
469 strbuf_addstr(sb, "\\n");
470 break;
471 case '\t':
472 strbuf_addstr(sb, "\\t");
473 break;
474 case '\v':
475 strbuf_addstr(sb, "\\v");
476 break;
477 }
478 }
479 strbuf_addch(sb, '"');
480 }
481
482 void basic_regex_quote_buf(struct strbuf *sb, const char *src)
483 {
484 char c;
485
486 if (*src == '^') {
487 /* only beginning '^' is special and needs quoting */
488 strbuf_addch(sb, '\\');
489 strbuf_addch(sb, *src++);
490 }
491 if (*src == '*')
492 /* beginning '*' is not special, no quoting */
493 strbuf_addch(sb, *src++);
494
495 while ((c = *src++)) {
496 switch (c) {
497 case '[':
498 case '.':
499 case '\\':
500 case '*':
501 strbuf_addch(sb, '\\');
502 strbuf_addch(sb, c);
503 break;
504
505 case '$':
506 /* only the end '$' is special and needs quoting */
507 if (*src == '\0')
508 strbuf_addch(sb, '\\');
509 strbuf_addch(sb, c);
510 break;
511
512 default:
513 strbuf_addch(sb, c);
514 break;
515 }
516 }
517 }