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 start with ^; all except
52 * ^<123> are two characters. The ones that are worth keeping are probably:
56 * <num> specified by number (decimal, 0octal, 0xHEX)
59 char ctrlparse(char *s
, char **next
)
68 } else if (*s
== '<') {
70 c
= (char)strtol(s
, next
, 0);
71 if ((*next
== s
) || (**next
!= '>')) {
76 } else if (*s
>= 'a' && *s
<= 'z') {
79 } else if ((*s
>= '@' && *s
<= '_') || *s
== '?' || (*s
& 0x80)) {
82 } else if (*s
== '~') {
90 /* ----------------------------------------------------------------------
91 * String handling routines.
94 char *dupstr(const char *s
)
99 p
= snewn(len
+ 1, char);
105 /* Allocate the concatenation of N strings. Terminate arg list with NULL. */
106 char *dupcat(const char *s1
, ...)
115 sn
= va_arg(ap
, char *);
122 p
= snewn(len
+ 1, char);
128 sn
= va_arg(ap
, char *);
140 * Do an sprintf(), but into a custom-allocated buffer.
142 * Currently I'm doing this via vsnprintf. This has worked so far,
143 * but it's not good, because:
145 * - vsnprintf is not available on all platforms. There's an ifdef
146 * to use `_vsnprintf', which seems to be the local name for it
147 * on Windows. Other platforms may lack it completely, in which
148 * case it'll be time to rewrite this function in a totally
151 * - technically you can't reuse a va_list like this: it is left
152 * unspecified whether advancing a va_list pointer modifies its
153 * value or something it points to, so on some platforms calling
154 * vsnprintf twice on the same va_list might fail hideously. It
155 * would be better to use the `va_copy' macro mandated by C99,
156 * but that too is not yet ubiquitous.
158 * The only `properly' portable solution I can think of is to
159 * implement my own format string scanner, which figures out an
160 * upper bound for the length of each formatting directive,
161 * allocates the buffer as it goes along, and calls sprintf() to
162 * actually process each directive. If I ever need to actually do
163 * this, some caveats:
165 * - It's very hard to find a reliable upper bound for
166 * floating-point values. %f, in particular, when supplied with
167 * a number near to the upper or lower limit of representable
168 * numbers, could easily take several hundred characters. It's
169 * probably feasible to predict this statically using the
170 * constants in <float.h>, or even to predict it dynamically by
171 * looking at the exponent of the specific float provided, but
174 * - Don't forget to _check_, after calling sprintf, that it's
175 * used at most the amount of space we had available.
177 * - Fault any formatting directive we don't fully understand. The
178 * aim here is to _guarantee_ that we never overflow the buffer,
179 * because this is a security-critical function. If we see a
180 * directive we don't know about, we should panic and die rather
183 char *dupprintf(const char *fmt
, ...)
188 ret
= dupvprintf(fmt
, ap
);
192 char *dupvprintf(const char *fmt
, va_list ap
)
197 buf
= snewn(512, char);
202 #define vsnprintf _vsnprintf
204 len
= vsnprintf(buf
, size
, fmt
, ap
);
205 if (len
>= 0 && len
< size
) {
206 /* This is the C99-specified criterion for snprintf to have
207 * been completely successful. */
209 } else if (len
> 0) {
210 /* This is the C99 error condition: the returned length is
211 * the required buffer size not counting the NUL. */
214 /* This is the pre-C99 glibc error condition: <0 means the
215 * buffer wasn't big enough, so we enlarge it a bit and hope. */
218 buf
= sresize(buf
, size
, char);
223 * Read an entire line of text from a file. Return a buffer
224 * malloced to be as big as necessary (caller must free).
226 char *fgetline(FILE *fp
)
228 char *ret
= snewn(512, char);
229 int size
= 512, len
= 0;
230 while (fgets(ret
+ len
, size
- len
, fp
)) {
231 len
+= strlen(ret
+ len
);
232 if (ret
[len
-1] == '\n')
233 break; /* got a newline, we're done */
235 ret
= sresize(ret
, size
, char);
237 if (len
== 0) { /* first fgets returned NULL */
245 /* ----------------------------------------------------------------------
246 * Base64 encoding routine. This is required in public-key writing
247 * but also in HTTP proxy handling, so it's centralised here.
250 void base64_encode_atom(unsigned char *data
, int n
, char *out
)
252 static const char base64_chars
[] =
253 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
257 word
= data
[0] << 16;
259 word
|= data
[1] << 8;
262 out
[0] = base64_chars
[(word
>> 18) & 0x3F];
263 out
[1] = base64_chars
[(word
>> 12) & 0x3F];
265 out
[2] = base64_chars
[(word
>> 6) & 0x3F];
269 out
[3] = base64_chars
[word
& 0x3F];
274 /* ----------------------------------------------------------------------
275 * Generic routines to deal with send buffers: a linked list of
276 * smallish blocks, with the operations
278 * - add an arbitrary amount of data to the end of the list
279 * - remove the first N bytes from the list
280 * - return a (pointer,length) pair giving some initial data in
281 * the list, suitable for passing to a send or write system
283 * - retrieve a larger amount of initial data from the list
284 * - return the current size of the buffer chain in bytes
287 #define BUFFER_GRANULE 512
289 struct bufchain_granule
{
290 struct bufchain_granule
*next
;
292 char buf
[BUFFER_GRANULE
];
295 void bufchain_init(bufchain
*ch
)
297 ch
->head
= ch
->tail
= NULL
;
301 void bufchain_clear(bufchain
*ch
)
303 struct bufchain_granule
*b
;
306 ch
->head
= ch
->head
->next
;
313 int bufchain_size(bufchain
*ch
)
315 return ch
->buffersize
;
318 void bufchain_add(bufchain
*ch
, const void *data
, int len
)
320 const char *buf
= (const char *)data
;
322 if (len
== 0) return;
324 ch
->buffersize
+= len
;
326 if (ch
->tail
&& ch
->tail
->buflen
< BUFFER_GRANULE
) {
327 int copylen
= min(len
, BUFFER_GRANULE
- ch
->tail
->buflen
);
328 memcpy(ch
->tail
->buf
+ ch
->tail
->buflen
, buf
, copylen
);
331 ch
->tail
->buflen
+= copylen
;
334 int grainlen
= min(len
, BUFFER_GRANULE
);
335 struct bufchain_granule
*newbuf
;
336 newbuf
= snew(struct bufchain_granule
);
338 newbuf
->buflen
= grainlen
;
339 memcpy(newbuf
->buf
, buf
, grainlen
);
343 ch
->tail
->next
= newbuf
;
345 ch
->head
= ch
->tail
= newbuf
;
351 void bufchain_consume(bufchain
*ch
, int len
)
353 struct bufchain_granule
*tmp
;
355 assert(ch
->buffersize
>= len
);
358 assert(ch
->head
!= NULL
);
359 if (remlen
>= ch
->head
->buflen
- ch
->head
->bufpos
) {
360 remlen
= ch
->head
->buflen
- ch
->head
->bufpos
;
362 ch
->head
= tmp
->next
;
367 ch
->head
->bufpos
+= remlen
;
368 ch
->buffersize
-= remlen
;
373 void bufchain_prefix(bufchain
*ch
, void **data
, int *len
)
375 *len
= ch
->head
->buflen
- ch
->head
->bufpos
;
376 *data
= ch
->head
->buf
+ ch
->head
->bufpos
;
379 void bufchain_fetch(bufchain
*ch
, void *data
, int len
)
381 struct bufchain_granule
*tmp
;
382 char *data_c
= (char *)data
;
386 assert(ch
->buffersize
>= len
);
391 if (remlen
>= tmp
->buflen
- tmp
->bufpos
)
392 remlen
= tmp
->buflen
- tmp
->bufpos
;
393 memcpy(data_c
, tmp
->buf
+ tmp
->bufpos
, remlen
);
401 /* ----------------------------------------------------------------------
402 * My own versions of malloc, realloc and free. Because I want
403 * malloc and realloc to bomb out and exit the program if they run
404 * out of memory, realloc to reliably call malloc if passed a NULL
405 * pointer, and free to reliably do nothing if passed a NULL
406 * pointer. We can also put trace printouts in, if we need to; and
407 * we can also replace the allocator with an ElectricFence-like
412 void *minefield_c_malloc(size_t size
);
413 void minefield_c_free(void *p
);
414 void *minefield_c_realloc(void *p
, size_t size
);
418 static FILE *fp
= NULL
;
420 static char *mlog_file
= NULL
;
421 static int mlog_line
= 0;
423 void mlog(char *file
, int line
)
428 fp
= fopen("putty_mem.log", "w");
429 setvbuf(fp
, NULL
, _IONBF
, BUFSIZ
);
432 fprintf(fp
, "%s:%d: ", file
, line
);
436 void *safemalloc(size_t n
, size_t size
)
440 if (n
> INT_MAX
/ size
) {
445 p
= minefield_c_malloc(size
);
454 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
455 mlog_file
, mlog_line
, size
);
456 fprintf(fp
, "*** %s\n", str
);
459 strcpy(str
, "Out of memory!");
465 fprintf(fp
, "malloc(%d) returns %p\n", size
, p
);
470 void *saferealloc(void *ptr
, size_t n
, size_t size
)
474 if (n
> INT_MAX
/ size
) {
480 p
= minefield_c_malloc(size
);
486 p
= minefield_c_realloc(ptr
, size
);
488 p
= realloc(ptr
, size
);
496 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
497 mlog_file
, mlog_line
, size
);
498 fprintf(fp
, "*** %s\n", str
);
501 strcpy(str
, "Out of memory!");
507 fprintf(fp
, "realloc(%p,%d) returns %p\n", ptr
, size
, p
);
512 void safefree(void *ptr
)
517 fprintf(fp
, "free(%p)\n", ptr
);
520 minefield_c_free(ptr
);
527 fprintf(fp
, "freeing null pointer - no action taken\n");
531 /* ----------------------------------------------------------------------
532 * Debugging routines.
536 extern void dputs(char *); /* defined in per-platform *misc.c */
538 void debug_printf(char *fmt
, ...)
544 buf
= dupvprintf(fmt
, ap
);
551 void debug_memdump(void *buf
, int len
, int L
)
554 unsigned char *p
= buf
;
558 debug_printf("\t%d (0x%x) bytes:\n", len
, len
);
559 delta
= 15 & (int) p
;
563 for (; 0 < len
; p
+= 16, len
-= 16) {
566 debug_printf("%p: ", p
);
567 strcpy(foo
, "................"); /* sixteen dots */
568 for (i
= 0; i
< 16 && i
< len
; ++i
) {
569 if (&p
[i
] < (unsigned char *) buf
) {
570 dputs(" "); /* 3 spaces */
573 debug_printf("%c%02.2x",
574 &p
[i
] != (unsigned char *) buf
575 && i
% 4 ?
'.' : ' ', p
[i
]
577 if (p
[i
] >= ' ' && p
[i
] <= '~')
578 foo
[i
] = (char) p
[i
];
582 debug_printf("%*s%s\n", (16 - i
) * 3 + 2, "", foo
);
586 #endif /* def DEBUG */