get_sha1_hex(): do not read past a NUL character
[alt-git.git] / quote.c
blob532fd3b7b7a0c7b6766a7af742b0c7362f307221
1 #include "cache.h"
2 #include "quote.h"
4 int quote_path_fully = 1;
6 /* Help to copy the thing properly quoted for the shell safety.
7 * any single quote is replaced with '\'', any exclamation point
8 * is replaced with '\!', and the whole thing is enclosed in a
10 * E.g.
11 * original sq_quote result
12 * name ==> name ==> 'name'
13 * a b ==> a b ==> 'a b'
14 * a'b ==> a'\''b ==> 'a'\''b'
15 * a!b ==> a'\!'b ==> 'a'\!'b'
17 static inline int need_bs_quote(char c)
19 return (c == '\'' || c == '!');
22 void sq_quote_buf(struct strbuf *dst, const char *src)
24 char *to_free = NULL;
26 if (dst->buf == src)
27 to_free = strbuf_detach(dst, NULL);
29 strbuf_addch(dst, '\'');
30 while (*src) {
31 size_t len = strcspn(src, "'!");
32 strbuf_add(dst, src, len);
33 src += len;
34 while (need_bs_quote(*src)) {
35 strbuf_addstr(dst, "'\\");
36 strbuf_addch(dst, *src++);
37 strbuf_addch(dst, '\'');
40 strbuf_addch(dst, '\'');
41 free(to_free);
44 void sq_quote_print(FILE *stream, const char *src)
46 char c;
48 fputc('\'', stream);
49 while ((c = *src++)) {
50 if (need_bs_quote(c)) {
51 fputs("'\\", stream);
52 fputc(c, stream);
53 fputc('\'', stream);
54 } else {
55 fputc(c, stream);
58 fputc('\'', stream);
61 void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
63 int i;
65 /* Copy into destination buffer. */
66 strbuf_grow(dst, 255);
67 for (i = 0; argv[i]; ++i) {
68 strbuf_addch(dst, ' ');
69 sq_quote_buf(dst, argv[i]);
70 if (maxlen && dst->len > maxlen)
71 die("Too many or long arguments");
75 static char *sq_dequote_step(char *arg, char **next)
77 char *dst = arg;
78 char *src = arg;
79 char c;
81 if (*src != '\'')
82 return NULL;
83 for (;;) {
84 c = *++src;
85 if (!c)
86 return NULL;
87 if (c != '\'') {
88 *dst++ = c;
89 continue;
91 /* We stepped out of sq */
92 switch (*++src) {
93 case '\0':
94 *dst = 0;
95 if (next)
96 *next = NULL;
97 return arg;
98 case '\\':
99 c = *++src;
100 if (need_bs_quote(c) && *++src == '\'') {
101 *dst++ = c;
102 continue;
104 /* Fallthrough */
105 default:
106 if (!next || !isspace(*src))
107 return NULL;
108 do {
109 c = *++src;
110 } while (isspace(c));
111 *dst = 0;
112 *next = src;
113 return arg;
118 char *sq_dequote(char *arg)
120 return sq_dequote_step(arg, NULL);
123 int sq_dequote_to_argv(char *arg, const char ***argv, int *nr, int *alloc)
125 char *next = arg;
127 if (!*arg)
128 return 0;
129 do {
130 char *dequoted = sq_dequote_step(next, &next);
131 if (!dequoted)
132 return -1;
133 ALLOC_GROW(*argv, *nr + 1, *alloc);
134 (*argv)[(*nr)++] = dequoted;
135 } while (next);
137 return 0;
140 /* 1 means: quote as octal
141 * 0 means: quote as octal if (quote_path_fully)
142 * -1 means: never quote
143 * c: quote as "\\c"
145 #define X8(x) x, x, x, x, x, x, x, x
146 #define X16(x) X8(x), X8(x)
147 static signed char const sq_lookup[256] = {
148 /* 0 1 2 3 4 5 6 7 */
149 /* 0x00 */ 1, 1, 1, 1, 1, 1, 1, 'a',
150 /* 0x08 */ 'b', 't', 'n', 'v', 'f', 'r', 1, 1,
151 /* 0x10 */ X16(1),
152 /* 0x20 */ -1, -1, '"', -1, -1, -1, -1, -1,
153 /* 0x28 */ X16(-1), X16(-1), X16(-1),
154 /* 0x58 */ -1, -1, -1, -1,'\\', -1, -1, -1,
155 /* 0x60 */ X16(-1), X8(-1),
156 /* 0x78 */ -1, -1, -1, -1, -1, -1, -1, 1,
157 /* 0x80 */ /* set to 0 */
160 static inline int sq_must_quote(char c)
162 return sq_lookup[(unsigned char)c] + quote_path_fully > 0;
165 /* returns the longest prefix not needing a quote up to maxlen if positive.
166 This stops at the first \0 because it's marked as a character needing an
167 escape */
168 static size_t next_quote_pos(const char *s, ssize_t maxlen)
170 size_t len;
171 if (maxlen < 0) {
172 for (len = 0; !sq_must_quote(s[len]); len++);
173 } else {
174 for (len = 0; len < maxlen && !sq_must_quote(s[len]); len++);
176 return len;
180 * C-style name quoting.
182 * (1) if sb and fp are both NULL, inspect the input name and counts the
183 * number of bytes that are needed to hold c_style quoted version of name,
184 * counting the double quotes around it but not terminating NUL, and
185 * returns it.
186 * However, if name does not need c_style quoting, it returns 0.
188 * (2) if sb or fp are not NULL, it emits the c_style quoted version
189 * of name, enclosed with double quotes if asked and needed only.
190 * Return value is the same as in (1).
192 static size_t quote_c_style_counted(const char *name, ssize_t maxlen,
193 struct strbuf *sb, FILE *fp, int no_dq)
195 #undef EMIT
196 #define EMIT(c) \
197 do { \
198 if (sb) strbuf_addch(sb, (c)); \
199 if (fp) fputc((c), fp); \
200 count++; \
201 } while (0)
202 #define EMITBUF(s, l) \
203 do { \
204 if (sb) strbuf_add(sb, (s), (l)); \
205 if (fp) fwrite((s), (l), 1, fp); \
206 count += (l); \
207 } while (0)
209 size_t len, count = 0;
210 const char *p = name;
212 for (;;) {
213 int ch;
215 len = next_quote_pos(p, maxlen);
216 if (len == maxlen || (maxlen < 0 && !p[len]))
217 break;
219 if (!no_dq && p == name)
220 EMIT('"');
222 EMITBUF(p, len);
223 EMIT('\\');
224 p += len;
225 ch = (unsigned char)*p++;
226 if (maxlen >= 0)
227 maxlen -= len + 1;
228 if (sq_lookup[ch] >= ' ') {
229 EMIT(sq_lookup[ch]);
230 } else {
231 EMIT(((ch >> 6) & 03) + '0');
232 EMIT(((ch >> 3) & 07) + '0');
233 EMIT(((ch >> 0) & 07) + '0');
237 EMITBUF(p, len);
238 if (p == name) /* no ending quote needed */
239 return 0;
241 if (!no_dq)
242 EMIT('"');
243 return count;
246 size_t quote_c_style(const char *name, struct strbuf *sb, FILE *fp, int nodq)
248 return quote_c_style_counted(name, -1, sb, fp, nodq);
251 void quote_two_c_style(struct strbuf *sb, const char *prefix, const char *path, int nodq)
253 if (quote_c_style(prefix, NULL, NULL, 0) ||
254 quote_c_style(path, NULL, NULL, 0)) {
255 if (!nodq)
256 strbuf_addch(sb, '"');
257 quote_c_style(prefix, sb, NULL, 1);
258 quote_c_style(path, sb, NULL, 1);
259 if (!nodq)
260 strbuf_addch(sb, '"');
261 } else {
262 strbuf_addstr(sb, prefix);
263 strbuf_addstr(sb, path);
267 void write_name_quoted(const char *name, FILE *fp, int terminator)
269 if (terminator) {
270 quote_c_style(name, NULL, fp, 0);
271 } else {
272 fputs(name, fp);
274 fputc(terminator, fp);
277 void write_name_quotedpfx(const char *pfx, size_t pfxlen,
278 const char *name, FILE *fp, int terminator)
280 int needquote = 0;
282 if (terminator) {
283 needquote = next_quote_pos(pfx, pfxlen) < pfxlen
284 || name[next_quote_pos(name, -1)];
286 if (needquote) {
287 fputc('"', fp);
288 quote_c_style_counted(pfx, pfxlen, NULL, fp, 1);
289 quote_c_style(name, NULL, fp, 1);
290 fputc('"', fp);
291 } else {
292 fwrite(pfx, pfxlen, 1, fp);
293 fputs(name, fp);
295 fputc(terminator, fp);
298 static const char *path_relative(const char *in, int len,
299 struct strbuf *sb, const char *prefix,
300 int prefix_len);
302 void write_name_quoted_relative(const char *name, size_t len,
303 const char *prefix, size_t prefix_len,
304 FILE *fp, int terminator)
306 struct strbuf sb = STRBUF_INIT;
308 name = path_relative(name, len, &sb, prefix, prefix_len);
309 write_name_quoted(name, fp, terminator);
311 strbuf_release(&sb);
315 * Give path as relative to prefix.
317 * The strbuf may or may not be used, so do not assume it contains the
318 * returned path.
320 static const char *path_relative(const char *in, int len,
321 struct strbuf *sb, const char *prefix,
322 int prefix_len)
324 int off, i;
326 if (len < 0)
327 len = strlen(in);
328 if (prefix_len < 0) {
329 if (prefix)
330 prefix_len = strlen(prefix);
331 else
332 prefix_len = 0;
335 off = 0;
336 i = 0;
337 while (i < prefix_len && i < len && prefix[i] == in[i]) {
338 if (prefix[i] == '/')
339 off = i + 1;
340 i++;
342 in += off;
343 len -= off;
345 if (i >= prefix_len)
346 return in;
348 strbuf_reset(sb);
349 strbuf_grow(sb, len);
351 while (i < prefix_len) {
352 if (prefix[i] == '/')
353 strbuf_addstr(sb, "../");
354 i++;
356 strbuf_add(sb, in, len);
358 return sb->buf;
361 /* quote path as relative to the given prefix */
362 char *quote_path_relative(const char *in, int len,
363 struct strbuf *out, const char *prefix)
365 struct strbuf sb = STRBUF_INIT;
366 const char *rel = path_relative(in, len, &sb, prefix, -1);
367 strbuf_reset(out);
368 quote_c_style_counted(rel, strlen(rel), out, NULL, 0);
369 strbuf_release(&sb);
371 if (!out->len)
372 strbuf_addstr(out, "./");
374 return out->buf;
378 * C-style name unquoting.
380 * Quoted should point at the opening double quote.
381 * + Returns 0 if it was able to unquote the string properly, and appends the
382 * result in the strbuf `sb'.
383 * + Returns -1 in case of error, and doesn't touch the strbuf. Though note
384 * that this function will allocate memory in the strbuf, so calling
385 * strbuf_release is mandatory whichever result unquote_c_style returns.
387 * Updates endp pointer to point at one past the ending double quote if given.
389 int unquote_c_style(struct strbuf *sb, const char *quoted, const char **endp)
391 size_t oldlen = sb->len, len;
392 int ch, ac;
394 if (*quoted++ != '"')
395 return -1;
397 for (;;) {
398 len = strcspn(quoted, "\"\\");
399 strbuf_add(sb, quoted, len);
400 quoted += len;
402 switch (*quoted++) {
403 case '"':
404 if (endp)
405 *endp = quoted;
406 return 0;
407 case '\\':
408 break;
409 default:
410 goto error;
413 switch ((ch = *quoted++)) {
414 case 'a': ch = '\a'; break;
415 case 'b': ch = '\b'; break;
416 case 'f': ch = '\f'; break;
417 case 'n': ch = '\n'; break;
418 case 'r': ch = '\r'; break;
419 case 't': ch = '\t'; break;
420 case 'v': ch = '\v'; break;
422 case '\\': case '"':
423 break; /* verbatim */
425 /* octal values with first digit over 4 overflow */
426 case '0': case '1': case '2': case '3':
427 ac = ((ch - '0') << 6);
428 if ((ch = *quoted++) < '0' || '7' < ch)
429 goto error;
430 ac |= ((ch - '0') << 3);
431 if ((ch = *quoted++) < '0' || '7' < ch)
432 goto error;
433 ac |= (ch - '0');
434 ch = ac;
435 break;
436 default:
437 goto error;
439 strbuf_addch(sb, ch);
442 error:
443 strbuf_setlen(sb, oldlen);
444 return -1;
447 /* quoting as a string literal for other languages */
449 void perl_quote_print(FILE *stream, const char *src)
451 const char sq = '\'';
452 const char bq = '\\';
453 char c;
455 fputc(sq, stream);
456 while ((c = *src++)) {
457 if (c == sq || c == bq)
458 fputc(bq, stream);
459 fputc(c, stream);
461 fputc(sq, stream);
464 void python_quote_print(FILE *stream, const char *src)
466 const char sq = '\'';
467 const char bq = '\\';
468 const char nl = '\n';
469 char c;
471 fputc(sq, stream);
472 while ((c = *src++)) {
473 if (c == nl) {
474 fputc(bq, stream);
475 fputc('n', stream);
476 continue;
478 if (c == sq || c == bq)
479 fputc(bq, stream);
480 fputc(c, stream);
482 fputc(sq, stream);
485 void tcl_quote_print(FILE *stream, const char *src)
487 char c;
489 fputc('"', stream);
490 while ((c = *src++)) {
491 switch (c) {
492 case '[': case ']':
493 case '{': case '}':
494 case '$': case '\\': case '"':
495 fputc('\\', stream);
496 default:
497 fputc(c, stream);
498 break;
499 case '\f':
500 fputs("\\f", stream);
501 break;
502 case '\r':
503 fputs("\\r", stream);
504 break;
505 case '\n':
506 fputs("\\n", stream);
507 break;
508 case '\t':
509 fputs("\\t", stream);
510 break;
511 case '\v':
512 fputs("\\v", stream);
513 break;
516 fputc('"', stream);