2 * Platform-independent routines shared between all PuTTY programs.
14 * Parse a string block size specification. This is approximately a
15 * subset of the block size specs supported by GNU fileutils:
19 * All numbers are decimal, and suffixes refer to powers of two.
22 unsigned long parse_blocksize(const char *bs)
25 unsigned long r = strtoul(bs, &suf, 10);
27 while (*suf && isspace((unsigned char)*suf)) suf++;
36 r *= 1024ul * 1024ul * 1024ul;
47 * Parse a ^C style character specification.
48 * Returns NULL in `next' if we didn't recognise it as a control character,
49 * in which case `c' should be ignored.
50 * The precise current parsing is an oddity inherited from the terminal
51 * answerback-string parsing code. All sequences are two characters,
52 * starting with '^'. The ones that are worth keeping are probably:
58 char ctrlparse(char *s, char **next)
69 } else if (*s >= 'a' && *s <= 'z') {
71 } else if ((*s >= '@' && *s <= '_') || *s == '?' || (*s & 0x80)) {
73 } else if (*s == '~') {
82 /* ----------------------------------------------------------------------
83 * String handling routines.
86 char *dupstr(const char *s)
91 p = snewn(len + 1, char);
97 /* Allocate the concatenation of N strings. Terminate arg list with NULL. */
98 char *dupcat(const char *s1, ...)
107 sn = va_arg(ap, char *);
114 p = snewn(len + 1, char);
120 sn = va_arg(ap, char *);
132 * Do an sprintf(), but into a custom-allocated buffer.
134 * Currently I'm doing this via vsnprintf. This has worked so far,
135 * but it's not good, because:
137 * - vsnprintf is not available on all platforms. There's an ifdef
138 * to use `_vsnprintf', which seems to be the local name for it
139 * on Windows. Other platforms may lack it completely, in which
140 * case it'll be time to rewrite this function in a totally
143 * - technically you can't reuse a va_list like this: it is left
144 * unspecified whether advancing a va_list pointer modifies its
145 * value or something it points to, so on some platforms calling
146 * vsnprintf twice on the same va_list might fail hideously. It
147 * would be better to use the `va_copy' macro mandated by C99,
148 * but that too is not yet ubiquitous.
150 * The only `properly' portable solution I can think of is to
151 * implement my own format string scanner, which figures out an
152 * upper bound for the length of each formatting directive,
153 * allocates the buffer as it goes along, and calls sprintf() to
154 * actually process each directive. If I ever need to actually do
155 * this, some caveats:
157 * - It's very hard to find a reliable upper bound for
158 * floating-point values. %f, in particular, when supplied with
159 * a number near to the upper or lower limit of representable
160 * numbers, could easily take several hundred characters. It's
161 * probably feasible to predict this statically using the
162 * constants in <float.h>, or even to predict it dynamically by
163 * looking at the exponent of the specific float provided, but
166 * - Don't forget to _check_, after calling sprintf, that it's
167 * used at most the amount of space we had available.
169 * - Fault any formatting directive we don't fully understand. The
170 * aim here is to _guarantee_ that we never overflow the buffer,
171 * because this is a security-critical function. If we see a
172 * directive we don't know about, we should panic and die rather
175 char *dupprintf(const char *fmt, ...)
180 ret = dupvprintf(fmt, ap);
184 char *dupvprintf(const char *fmt, va_list ap)
189 buf = snewn(512, char);
194 #define vsnprintf _vsnprintf
196 len = vsnprintf(buf, size, fmt, ap);
197 if (len >= 0 && len < size) {
198 /* This is the C99-specified criterion for snprintf to have
199 * been completely successful. */
201 } else if (len > 0) {
202 /* This is the C99 error condition: the returned length is
203 * the required buffer size not counting the NUL. */
206 /* This is the pre-C99 glibc error condition: <0 means the
207 * buffer wasn't big enough, so we enlarge it a bit and hope. */
210 buf = sresize(buf, size, char);
215 * Read an entire line of text from a file. Return a buffer
216 * malloced to be as big as necessary (caller must free).
218 char *fgetline(FILE *fp)
220 char *ret = snewn(512, char);
221 int size = 512, len = 0;
222 while (fgets(ret + len, size - len, fp)) {
223 len += strlen(ret + len);
224 if (ret[len-1] == '\n')
225 break; /* got a newline, we're done */
227 ret = sresize(ret, size, char);
229 if (len == 0) { /* first fgets returned NULL */
237 /* ----------------------------------------------------------------------
238 * Base64 encoding routine. This is required in public-key writing
239 * but also in HTTP proxy handling, so it's centralised here.
242 void base64_encode_atom(unsigned char *data, int n, char *out)
244 static const char base64_chars[] =
245 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
249 word = data[0] << 16;
251 word |= data[1] << 8;
254 out[0] = base64_chars[(word >> 18) & 0x3F];
255 out[1] = base64_chars[(word >> 12) & 0x3F];
257 out[2] = base64_chars[(word >> 6) & 0x3F];
261 out[3] = base64_chars[word & 0x3F];
266 /* ----------------------------------------------------------------------
267 * Generic routines to deal with send buffers: a linked list of
268 * smallish blocks, with the operations
270 * - add an arbitrary amount of data to the end of the list
271 * - remove the first N bytes from the list
272 * - return a (pointer,length) pair giving some initial data in
273 * the list, suitable for passing to a send or write system
275 * - retrieve a larger amount of initial data from the list
276 * - return the current size of the buffer chain in bytes
279 #define BUFFER_GRANULE 512
281 struct bufchain_granule {
282 struct bufchain_granule *next;
284 char buf[BUFFER_GRANULE];
287 void bufchain_init(bufchain *ch)
289 ch->head = ch->tail = NULL;
293 void bufchain_clear(bufchain *ch)
295 struct bufchain_granule *b;
298 ch->head = ch->head->next;
305 int bufchain_size(bufchain *ch)
307 return ch->buffersize;
310 void bufchain_add(bufchain *ch, const void *data, int len)
312 const char *buf = (const char *)data;
314 if (len == 0) return;
316 ch->buffersize += len;
318 if (ch->tail && ch->tail->buflen < BUFFER_GRANULE) {
319 int copylen = min(len, BUFFER_GRANULE - ch->tail->buflen);
320 memcpy(ch->tail->buf + ch->tail->buflen, buf, copylen);
323 ch->tail->buflen += copylen;
326 int grainlen = min(len, BUFFER_GRANULE);
327 struct bufchain_granule *newbuf;
328 newbuf = snew(struct bufchain_granule);
330 newbuf->buflen = grainlen;
331 memcpy(newbuf->buf, buf, grainlen);
335 ch->tail->next = newbuf;
337 ch->head = ch->tail = newbuf;
343 void bufchain_consume(bufchain *ch, int len)
345 struct bufchain_granule *tmp;
347 assert(ch->buffersize >= len);
350 assert(ch->head != NULL);
351 if (remlen >= ch->head->buflen - ch->head->bufpos) {
352 remlen = ch->head->buflen - ch->head->bufpos;
354 ch->head = tmp->next;
359 ch->head->bufpos += remlen;
360 ch->buffersize -= remlen;
365 void bufchain_prefix(bufchain *ch, void **data, int *len)
367 *len = ch->head->buflen - ch->head->bufpos;
368 *data = ch->head->buf + ch->head->bufpos;
371 void bufchain_fetch(bufchain *ch, void *data, int len)
373 struct bufchain_granule *tmp;
374 char *data_c = (char *)data;
378 assert(ch->buffersize >= len);
383 if (remlen >= tmp->buflen - tmp->bufpos)
384 remlen = tmp->buflen - tmp->bufpos;
385 memcpy(data_c, tmp->buf + tmp->bufpos, remlen);
393 /* ----------------------------------------------------------------------
394 * My own versions of malloc, realloc and free. Because I want
395 * malloc and realloc to bomb out and exit the program if they run
396 * out of memory, realloc to reliably call malloc if passed a NULL
397 * pointer, and free to reliably do nothing if passed a NULL
398 * pointer. We can also put trace printouts in, if we need to; and
399 * we can also replace the allocator with an ElectricFence-like
404 void *minefield_c_malloc(size_t size);
405 void minefield_c_free(void *p);
406 void *minefield_c_realloc(void *p, size_t size);
410 static FILE *fp = NULL;
412 static char *mlog_file = NULL;
413 static int mlog_line = 0;
415 void mlog(char *file, int line)
420 fp = fopen("putty_mem.log", "w");
421 setvbuf(fp, NULL, _IONBF, BUFSIZ);
424 fprintf(fp, "%s:%d: ", file, line);
428 void *safemalloc(size_t n, size_t size)
432 if (n > INT_MAX / size) {
437 p = minefield_c_malloc(size);
446 sprintf(str, "Out of memory! (%s:%d, size=%d)",
447 mlog_file, mlog_line, size);
448 fprintf(fp, "*** %s\n", str);
451 strcpy(str, "Out of memory!");
457 fprintf(fp, "malloc(%d) returns %p\n", size, p);
462 void *saferealloc(void *ptr, size_t n, size_t size)
466 if (n > INT_MAX / size) {
472 p = minefield_c_malloc(size);
478 p = minefield_c_realloc(ptr, size);
480 p = realloc(ptr, size);
488 sprintf(str, "Out of memory! (%s:%d, size=%d)",
489 mlog_file, mlog_line, size);
490 fprintf(fp, "*** %s\n", str);
493 strcpy(str, "Out of memory!");
499 fprintf(fp, "realloc(%p,%d) returns %p\n", ptr, size, p);
504 void safefree(void *ptr)
509 fprintf(fp, "free(%p)\n", ptr);
512 minefield_c_free(ptr);
519 fprintf(fp, "freeing null pointer - no action taken\n");
523 /* ----------------------------------------------------------------------
524 * Debugging routines.
528 extern void dputs(char *); /* defined in per-platform *misc.c */
530 void debug_printf(char *fmt, ...)
536 buf = dupvprintf(fmt, ap);
543 void debug_memdump(void *buf, int len, int L)
546 unsigned char *p = buf;
550 debug_printf("\t%d (0x%x) bytes:\n", len, len);
551 delta = 15 & (int) p;
555 for (; 0 < len; p += 16, len -= 16) {
558 debug_printf("%p: ", p);
559 strcpy(foo, "................"); /* sixteen dots */
560 for (i = 0; i < 16 && i < len; ++i) {
561 if (&p[i] < (unsigned char *) buf) {
562 dputs(" "); /* 3 spaces */
565 debug_printf("%c%02.2x",
566 &p[i] != (unsigned char *) buf
567 && i % 4 ? '.' : ' ', p[i]
569 if (p[i] >= ' ' && p[i] <= '~')
570 foo[i] = (char) p[i];
574 debug_printf("%*s%s\n", (16 - i) * 3 + 2, "", foo);
578 #endif /* def DEBUG */