f4ff9455 |
1 | /* |
2 | * Platform-independent routines shared between all PuTTY programs. |
3 | */ |
4 | |
374330e2 |
5 | #include <stdio.h> |
6 | #include <stdlib.h> |
1709795f |
7 | #include <stdarg.h> |
57356d63 |
8 | #include <ctype.h> |
5471d09a |
9 | #include <assert.h> |
374330e2 |
10 | #include "putty.h" |
11 | |
03f64569 |
12 | /* ---------------------------------------------------------------------- |
13 | * String handling routines. |
14 | */ |
15 | |
57356d63 |
16 | char *dupstr(const char *s) |
03f64569 |
17 | { |
6d113886 |
18 | char *p = NULL; |
19 | if (s) { |
20 | int len = strlen(s); |
21 | p = snewn(len + 1, char); |
22 | strcpy(p, s); |
23 | } |
03f64569 |
24 | return p; |
25 | } |
26 | |
27 | /* Allocate the concatenation of N strings. Terminate arg list with NULL. */ |
57356d63 |
28 | char *dupcat(const char *s1, ...) |
03f64569 |
29 | { |
30 | int len; |
31 | char *p, *q, *sn; |
32 | va_list ap; |
33 | |
34 | len = strlen(s1); |
35 | va_start(ap, s1); |
36 | while (1) { |
37 | sn = va_arg(ap, char *); |
38 | if (!sn) |
39 | break; |
40 | len += strlen(sn); |
41 | } |
42 | va_end(ap); |
43 | |
3d88e64d |
44 | p = snewn(len + 1, char); |
03f64569 |
45 | strcpy(p, s1); |
46 | q = p + strlen(p); |
47 | |
48 | va_start(ap, s1); |
49 | while (1) { |
50 | sn = va_arg(ap, char *); |
51 | if (!sn) |
52 | break; |
53 | strcpy(q, sn); |
54 | q += strlen(q); |
55 | } |
56 | va_end(ap); |
57 | |
58 | return p; |
59 | } |
60 | |
57356d63 |
61 | /* |
62 | * Do an sprintf(), but into a custom-allocated buffer. |
63 | * |
28da9e3d |
64 | * Currently I'm doing this via vsnprintf. This has worked so far, |
65 | * but it's not good, because: |
66 | * |
67 | * - vsnprintf is not available on all platforms. There's an ifdef |
68 | * to use `_vsnprintf', which seems to be the local name for it |
69 | * on Windows. Other platforms may lack it completely, in which |
70 | * case it'll be time to rewrite this function in a totally |
71 | * different way. |
72 | * |
73 | * - technically you can't reuse a va_list like this: it is left |
74 | * unspecified whether advancing a va_list pointer modifies its |
75 | * value or something it points to, so on some platforms calling |
76 | * vsnprintf twice on the same va_list might fail hideously. It |
77 | * would be better to use the `va_copy' macro mandated by C99, |
78 | * but that too is not yet ubiquitous. |
79 | * |
80 | * The only `properly' portable solution I can think of is to |
81 | * implement my own format string scanner, which figures out an |
82 | * upper bound for the length of each formatting directive, |
83 | * allocates the buffer as it goes along, and calls sprintf() to |
84 | * actually process each directive. If I ever need to actually do |
85 | * this, some caveats: |
86 | * |
87 | * - It's very hard to find a reliable upper bound for |
88 | * floating-point values. %f, in particular, when supplied with |
89 | * a number near to the upper or lower limit of representable |
90 | * numbers, could easily take several hundred characters. It's |
91 | * probably feasible to predict this statically using the |
92 | * constants in <float.h>, or even to predict it dynamically by |
93 | * looking at the exponent of the specific float provided, but |
94 | * it won't be fun. |
95 | * |
96 | * - Don't forget to _check_, after calling sprintf, that it's |
97 | * used at most the amount of space we had available. |
98 | * |
99 | * - Fault any formatting directive we don't fully understand. The |
100 | * aim here is to _guarantee_ that we never overflow the buffer, |
101 | * because this is a security-critical function. If we see a |
102 | * directive we don't know about, we should panic and die rather |
103 | * than run any risk. |
57356d63 |
104 | */ |
105 | char *dupprintf(const char *fmt, ...) |
106 | { |
107 | char *ret; |
108 | va_list ap; |
109 | va_start(ap, fmt); |
110 | ret = dupvprintf(fmt, ap); |
111 | va_end(ap); |
112 | return ret; |
113 | } |
114 | char *dupvprintf(const char *fmt, va_list ap) |
115 | { |
116 | char *buf; |
117 | int len, size; |
118 | |
3d88e64d |
119 | buf = snewn(512, char); |
57356d63 |
120 | size = 512; |
121 | |
122 | while (1) { |
123 | #ifdef _WINDOWS |
124 | #define vsnprintf _vsnprintf |
125 | #endif |
126 | len = vsnprintf(buf, size, fmt, ap); |
127 | if (len >= 0 && len < size) { |
128 | /* This is the C99-specified criterion for snprintf to have |
129 | * been completely successful. */ |
130 | return buf; |
131 | } else if (len > 0) { |
132 | /* This is the C99 error condition: the returned length is |
133 | * the required buffer size not counting the NUL. */ |
134 | size = len + 1; |
135 | } else { |
136 | /* This is the pre-C99 glibc error condition: <0 means the |
137 | * buffer wasn't big enough, so we enlarge it a bit and hope. */ |
138 | size += 512; |
139 | } |
3d88e64d |
140 | buf = sresize(buf, size, char); |
57356d63 |
141 | } |
142 | } |
143 | |
39934deb |
144 | /* |
145 | * Read an entire line of text from a file. Return a buffer |
146 | * malloced to be as big as necessary (caller must free). |
147 | */ |
148 | char *fgetline(FILE *fp) |
149 | { |
150 | char *ret = snewn(512, char); |
151 | int size = 512, len = 0; |
152 | while (fgets(ret + len, size - len, fp)) { |
153 | len += strlen(ret + len); |
154 | if (ret[len-1] == '\n') |
155 | break; /* got a newline, we're done */ |
156 | size = len + 512; |
157 | ret = sresize(ret, size, char); |
158 | } |
159 | if (len == 0) { /* first fgets returned NULL */ |
160 | sfree(ret); |
161 | return NULL; |
162 | } |
163 | ret[len] = '\0'; |
164 | return ret; |
165 | } |
166 | |
03f64569 |
167 | /* ---------------------------------------------------------------------- |
1549e076 |
168 | * Base64 encoding routine. This is required in public-key writing |
169 | * but also in HTTP proxy handling, so it's centralised here. |
170 | */ |
171 | |
172 | void base64_encode_atom(unsigned char *data, int n, char *out) |
173 | { |
174 | static const char base64_chars[] = |
175 | "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; |
176 | |
177 | unsigned word; |
178 | |
179 | word = data[0] << 16; |
180 | if (n > 1) |
181 | word |= data[1] << 8; |
182 | if (n > 2) |
183 | word |= data[2]; |
184 | out[0] = base64_chars[(word >> 18) & 0x3F]; |
185 | out[1] = base64_chars[(word >> 12) & 0x3F]; |
186 | if (n > 1) |
187 | out[2] = base64_chars[(word >> 6) & 0x3F]; |
188 | else |
189 | out[2] = '='; |
190 | if (n > 2) |
191 | out[3] = base64_chars[word & 0x3F]; |
192 | else |
193 | out[3] = '='; |
194 | } |
195 | |
196 | /* ---------------------------------------------------------------------- |
5471d09a |
197 | * Generic routines to deal with send buffers: a linked list of |
198 | * smallish blocks, with the operations |
199 | * |
200 | * - add an arbitrary amount of data to the end of the list |
201 | * - remove the first N bytes from the list |
202 | * - return a (pointer,length) pair giving some initial data in |
203 | * the list, suitable for passing to a send or write system |
204 | * call |
7983f47e |
205 | * - retrieve a larger amount of initial data from the list |
5471d09a |
206 | * - return the current size of the buffer chain in bytes |
207 | */ |
208 | |
209 | #define BUFFER_GRANULE 512 |
210 | |
211 | struct bufchain_granule { |
212 | struct bufchain_granule *next; |
213 | int buflen, bufpos; |
214 | char buf[BUFFER_GRANULE]; |
215 | }; |
216 | |
217 | void bufchain_init(bufchain *ch) |
218 | { |
219 | ch->head = ch->tail = NULL; |
220 | ch->buffersize = 0; |
221 | } |
222 | |
223 | void bufchain_clear(bufchain *ch) |
224 | { |
225 | struct bufchain_granule *b; |
226 | while (ch->head) { |
227 | b = ch->head; |
228 | ch->head = ch->head->next; |
229 | sfree(b); |
230 | } |
231 | ch->tail = NULL; |
232 | ch->buffersize = 0; |
233 | } |
234 | |
235 | int bufchain_size(bufchain *ch) |
236 | { |
237 | return ch->buffersize; |
238 | } |
239 | |
e0e7dff8 |
240 | void bufchain_add(bufchain *ch, const void *data, int len) |
5471d09a |
241 | { |
e0e7dff8 |
242 | const char *buf = (const char *)data; |
5471d09a |
243 | |
bfa5400d |
244 | if (len == 0) return; |
245 | |
5471d09a |
246 | ch->buffersize += len; |
247 | |
248 | if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) { |
249 | int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen); |
250 | memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen); |
251 | buf += copylen; |
252 | len -= copylen; |
253 | ch->tail->buflen += copylen; |
254 | } |
255 | while (len > 0) { |
256 | int grainlen = min(len, BUFFER_GRANULE); |
257 | struct bufchain_granule *newbuf; |
3d88e64d |
258 | newbuf = snew(struct bufchain_granule); |
5471d09a |
259 | newbuf->bufpos = 0; |
260 | newbuf->buflen = grainlen; |
261 | memcpy(newbuf->buf, buf, grainlen); |
262 | buf += grainlen; |
263 | len -= grainlen; |
264 | if (ch->tail) |
265 | ch->tail->next = newbuf; |
266 | else |
267 | ch->head = ch->tail = newbuf; |
268 | newbuf->next = NULL; |
269 | ch->tail = newbuf; |
270 | } |
271 | } |
272 | |
273 | void bufchain_consume(bufchain *ch, int len) |
274 | { |
7983f47e |
275 | struct bufchain_granule *tmp; |
276 | |
5471d09a |
277 | assert(ch->buffersize >= len); |
7983f47e |
278 | while (len > 0) { |
279 | int remlen = len; |
280 | assert(ch->head != NULL); |
281 | if (remlen >= ch->head->buflen - ch->head->bufpos) { |
282 | remlen = ch->head->buflen - ch->head->bufpos; |
283 | tmp = ch->head; |
284 | ch->head = tmp->next; |
285 | sfree(tmp); |
286 | if (!ch->head) |
287 | ch->tail = NULL; |
288 | } else |
289 | ch->head->bufpos += remlen; |
290 | ch->buffersize -= remlen; |
291 | len -= remlen; |
5471d09a |
292 | } |
293 | } |
294 | |
295 | void bufchain_prefix(bufchain *ch, void **data, int *len) |
296 | { |
297 | *len = ch->head->buflen - ch->head->bufpos; |
298 | *data = ch->head->buf + ch->head->bufpos; |
299 | } |
300 | |
7983f47e |
301 | void bufchain_fetch(bufchain *ch, void *data, int len) |
302 | { |
303 | struct bufchain_granule *tmp; |
304 | char *data_c = (char *)data; |
305 | |
306 | tmp = ch->head; |
307 | |
308 | assert(ch->buffersize >= len); |
309 | while (len > 0) { |
310 | int remlen = len; |
311 | |
312 | assert(tmp != NULL); |
313 | if (remlen >= tmp->buflen - tmp->bufpos) |
314 | remlen = tmp->buflen - tmp->bufpos; |
315 | memcpy(data_c, tmp->buf + tmp->bufpos, remlen); |
316 | |
317 | tmp = tmp->next; |
318 | len -= remlen; |
319 | data_c += remlen; |
320 | } |
321 | } |
322 | |
03f64569 |
323 | /* ---------------------------------------------------------------------- |
b191636d |
324 | * My own versions of malloc, realloc and free. Because I want |
325 | * malloc and realloc to bomb out and exit the program if they run |
326 | * out of memory, realloc to reliably call malloc if passed a NULL |
327 | * pointer, and free to reliably do nothing if passed a NULL |
328 | * pointer. We can also put trace printouts in, if we need to; and |
329 | * we can also replace the allocator with an ElectricFence-like |
330 | * one. |
331 | */ |
332 | |
333 | #ifdef MINEFIELD |
d0912d1f |
334 | void *minefield_c_malloc(size_t size); |
335 | void minefield_c_free(void *p); |
336 | void *minefield_c_realloc(void *p, size_t size); |
337 | #endif |
374330e2 |
338 | |
339 | #ifdef MALLOC_LOG |
340 | static FILE *fp = NULL; |
341 | |
d7da76ca |
342 | static char *mlog_file = NULL; |
343 | static int mlog_line = 0; |
344 | |
32874aea |
345 | void mlog(char *file, int line) |
346 | { |
d7da76ca |
347 | mlog_file = file; |
348 | mlog_line = line; |
c662dbc0 |
349 | if (!fp) { |
374330e2 |
350 | fp = fopen("putty_mem.log", "w"); |
c662dbc0 |
351 | setvbuf(fp, NULL, _IONBF, BUFSIZ); |
352 | } |
374330e2 |
353 | if (fp) |
32874aea |
354 | fprintf(fp, "%s:%d: ", file, line); |
374330e2 |
355 | } |
356 | #endif |
357 | |
32874aea |
358 | void *safemalloc(size_t size) |
359 | { |
b191636d |
360 | void *p; |
361 | #ifdef MINEFIELD |
32874aea |
362 | p = minefield_c_malloc(size); |
b191636d |
363 | #else |
32874aea |
364 | p = malloc(size); |
b191636d |
365 | #endif |
374330e2 |
366 | if (!p) { |
d7da76ca |
367 | char str[200]; |
368 | #ifdef MALLOC_LOG |
369 | sprintf(str, "Out of memory! (%s:%d, size=%d)", |
370 | mlog_file, mlog_line, size); |
1b2ef365 |
371 | fprintf(fp, "*** %s\n", str); |
372 | fclose(fp); |
d7da76ca |
373 | #else |
374 | strcpy(str, "Out of memory!"); |
375 | #endif |
1709795f |
376 | modalfatalbox(str); |
374330e2 |
377 | } |
378 | #ifdef MALLOC_LOG |
379 | if (fp) |
380 | fprintf(fp, "malloc(%d) returns %p\n", size, p); |
381 | #endif |
382 | return p; |
383 | } |
384 | |
32874aea |
385 | void *saferealloc(void *ptr, size_t size) |
386 | { |
374330e2 |
387 | void *p; |
b191636d |
388 | if (!ptr) { |
389 | #ifdef MINEFIELD |
32874aea |
390 | p = minefield_c_malloc(size); |
b191636d |
391 | #else |
32874aea |
392 | p = malloc(size); |
b191636d |
393 | #endif |
394 | } else { |
395 | #ifdef MINEFIELD |
32874aea |
396 | p = minefield_c_realloc(ptr, size); |
b191636d |
397 | #else |
32874aea |
398 | p = realloc(ptr, size); |
b191636d |
399 | #endif |
400 | } |
374330e2 |
401 | if (!p) { |
d7da76ca |
402 | char str[200]; |
403 | #ifdef MALLOC_LOG |
404 | sprintf(str, "Out of memory! (%s:%d, size=%d)", |
405 | mlog_file, mlog_line, size); |
1b2ef365 |
406 | fprintf(fp, "*** %s\n", str); |
407 | fclose(fp); |
d7da76ca |
408 | #else |
409 | strcpy(str, "Out of memory!"); |
410 | #endif |
1709795f |
411 | modalfatalbox(str); |
374330e2 |
412 | } |
413 | #ifdef MALLOC_LOG |
414 | if (fp) |
415 | fprintf(fp, "realloc(%p,%d) returns %p\n", ptr, size, p); |
416 | #endif |
417 | return p; |
418 | } |
419 | |
32874aea |
420 | void safefree(void *ptr) |
421 | { |
374330e2 |
422 | if (ptr) { |
423 | #ifdef MALLOC_LOG |
424 | if (fp) |
425 | fprintf(fp, "free(%p)\n", ptr); |
426 | #endif |
b191636d |
427 | #ifdef MINEFIELD |
32874aea |
428 | minefield_c_free(ptr); |
b191636d |
429 | #else |
32874aea |
430 | free(ptr); |
b191636d |
431 | #endif |
374330e2 |
432 | } |
433 | #ifdef MALLOC_LOG |
434 | else if (fp) |
435 | fprintf(fp, "freeing null pointer - no action taken\n"); |
436 | #endif |
437 | } |
c82bda52 |
438 | |
03f64569 |
439 | /* ---------------------------------------------------------------------- |
440 | * Debugging routines. |
441 | */ |
442 | |
c82bda52 |
443 | #ifdef DEBUG |
d0912d1f |
444 | extern void dputs(char *); /* defined in per-platform *misc.c */ |
db9c0f86 |
445 | |
d0912d1f |
446 | void debug_printf(char *fmt, ...) |
32874aea |
447 | { |
57356d63 |
448 | char *buf; |
db9c0f86 |
449 | va_list ap; |
450 | |
451 | va_start(ap, fmt); |
57356d63 |
452 | buf = dupvprintf(fmt, ap); |
32874aea |
453 | dputs(buf); |
57356d63 |
454 | sfree(buf); |
c82bda52 |
455 | va_end(ap); |
456 | } |
db9c0f86 |
457 | |
458 | |
32874aea |
459 | void debug_memdump(void *buf, int len, int L) |
460 | { |
db9c0f86 |
461 | int i; |
462 | unsigned char *p = buf; |
765c4200 |
463 | char foo[17]; |
db9c0f86 |
464 | if (L) { |
465 | int delta; |
d0912d1f |
466 | debug_printf("\t%d (0x%x) bytes:\n", len, len); |
db9c0f86 |
467 | delta = 15 & (int) p; |
468 | p -= delta; |
469 | len += delta; |
470 | } |
471 | for (; 0 < len; p += 16, len -= 16) { |
32874aea |
472 | dputs(" "); |
473 | if (L) |
d0912d1f |
474 | debug_printf("%p: ", p); |
32874aea |
475 | strcpy(foo, "................"); /* sixteen dots */ |
db9c0f86 |
476 | for (i = 0; i < 16 && i < len; ++i) { |
477 | if (&p[i] < (unsigned char *) buf) { |
32874aea |
478 | dputs(" "); /* 3 spaces */ |
765c4200 |
479 | foo[i] = ' '; |
db9c0f86 |
480 | } else { |
d0912d1f |
481 | debug_printf("%c%02.2x", |
32874aea |
482 | &p[i] != (unsigned char *) buf |
483 | && i % 4 ? '.' : ' ', p[i] |
484 | ); |
765c4200 |
485 | if (p[i] >= ' ' && p[i] <= '~') |
32874aea |
486 | foo[i] = (char) p[i]; |
db9c0f86 |
487 | } |
488 | } |
765c4200 |
489 | foo[i] = '\0'; |
d0912d1f |
490 | debug_printf("%*s%s\n", (16 - i) * 3 + 2, "", foo); |
db9c0f86 |
491 | } |
492 | } |
493 | |
32874aea |
494 | #endif /* def DEBUG */ |