2 * Platform-independent routines shared between all PuTTY programs.
13 * Parse a string block size specification. This is approximately a
14 * subset of the block size specs supported by GNU fileutils:
18 * All numbers are decimal, and suffixes refer to powers of two.
21 unsigned long parse_blocksize(const char *bs
)
24 unsigned long r
= strtoul(bs
, &suf
, 10);
26 while (isspace(*suf
)) suf
++;
35 r
*= 1024ul * 1024ul * 1024ul;
45 /* ----------------------------------------------------------------------
46 * String handling routines.
49 char *dupstr(const char *s
)
54 p
= snewn(len
+ 1, char);
60 /* Allocate the concatenation of N strings. Terminate arg list with NULL. */
61 char *dupcat(const char *s1
, ...)
70 sn
= va_arg(ap
, char *);
77 p
= snewn(len
+ 1, char);
83 sn
= va_arg(ap
, char *);
95 * Do an sprintf(), but into a custom-allocated buffer.
97 * Currently I'm doing this via vsnprintf. This has worked so far,
98 * but it's not good, because:
100 * - vsnprintf is not available on all platforms. There's an ifdef
101 * to use `_vsnprintf', which seems to be the local name for it
102 * on Windows. Other platforms may lack it completely, in which
103 * case it'll be time to rewrite this function in a totally
106 * - technically you can't reuse a va_list like this: it is left
107 * unspecified whether advancing a va_list pointer modifies its
108 * value or something it points to, so on some platforms calling
109 * vsnprintf twice on the same va_list might fail hideously. It
110 * would be better to use the `va_copy' macro mandated by C99,
111 * but that too is not yet ubiquitous.
113 * The only `properly' portable solution I can think of is to
114 * implement my own format string scanner, which figures out an
115 * upper bound for the length of each formatting directive,
116 * allocates the buffer as it goes along, and calls sprintf() to
117 * actually process each directive. If I ever need to actually do
118 * this, some caveats:
120 * - It's very hard to find a reliable upper bound for
121 * floating-point values. %f, in particular, when supplied with
122 * a number near to the upper or lower limit of representable
123 * numbers, could easily take several hundred characters. It's
124 * probably feasible to predict this statically using the
125 * constants in <float.h>, or even to predict it dynamically by
126 * looking at the exponent of the specific float provided, but
129 * - Don't forget to _check_, after calling sprintf, that it's
130 * used at most the amount of space we had available.
132 * - Fault any formatting directive we don't fully understand. The
133 * aim here is to _guarantee_ that we never overflow the buffer,
134 * because this is a security-critical function. If we see a
135 * directive we don't know about, we should panic and die rather
138 char *dupprintf(const char *fmt
, ...)
143 ret
= dupvprintf(fmt
, ap
);
147 char *dupvprintf(const char *fmt
, va_list ap
)
152 buf
= snewn(512, char);
157 #define vsnprintf _vsnprintf
159 len
= vsnprintf(buf
, size
, fmt
, ap
);
160 if (len
>= 0 && len
< size
) {
161 /* This is the C99-specified criterion for snprintf to have
162 * been completely successful. */
164 } else if (len
> 0) {
165 /* This is the C99 error condition: the returned length is
166 * the required buffer size not counting the NUL. */
169 /* This is the pre-C99 glibc error condition: <0 means the
170 * buffer wasn't big enough, so we enlarge it a bit and hope. */
173 buf
= sresize(buf
, size
, char);
178 * Read an entire line of text from a file. Return a buffer
179 * malloced to be as big as necessary (caller must free).
181 char *fgetline(FILE *fp
)
183 char *ret
= snewn(512, char);
184 int size
= 512, len
= 0;
185 while (fgets(ret
+ len
, size
- len
, fp
)) {
186 len
+= strlen(ret
+ len
);
187 if (ret
[len
-1] == '\n')
188 break; /* got a newline, we're done */
190 ret
= sresize(ret
, size
, char);
192 if (len
== 0) { /* first fgets returned NULL */
200 /* ----------------------------------------------------------------------
201 * Base64 encoding routine. This is required in public-key writing
202 * but also in HTTP proxy handling, so it's centralised here.
205 void base64_encode_atom(unsigned char *data
, int n
, char *out
)
207 static const char base64_chars
[] =
208 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
212 word
= data
[0] << 16;
214 word
|= data
[1] << 8;
217 out
[0] = base64_chars
[(word
>> 18) & 0x3F];
218 out
[1] = base64_chars
[(word
>> 12) & 0x3F];
220 out
[2] = base64_chars
[(word
>> 6) & 0x3F];
224 out
[3] = base64_chars
[word
& 0x3F];
229 /* ----------------------------------------------------------------------
230 * Generic routines to deal with send buffers: a linked list of
231 * smallish blocks, with the operations
233 * - add an arbitrary amount of data to the end of the list
234 * - remove the first N bytes from the list
235 * - return a (pointer,length) pair giving some initial data in
236 * the list, suitable for passing to a send or write system
238 * - retrieve a larger amount of initial data from the list
239 * - return the current size of the buffer chain in bytes
242 #define BUFFER_GRANULE 512
244 struct bufchain_granule
{
245 struct bufchain_granule
*next
;
247 char buf
[BUFFER_GRANULE
];
250 void bufchain_init(bufchain
*ch
)
252 ch
->head
= ch
->tail
= NULL
;
256 void bufchain_clear(bufchain
*ch
)
258 struct bufchain_granule
*b
;
261 ch
->head
= ch
->head
->next
;
268 int bufchain_size(bufchain
*ch
)
270 return ch
->buffersize
;
273 void bufchain_add(bufchain
*ch
, const void *data
, int len
)
275 const char *buf
= (const char *)data
;
277 if (len
== 0) return;
279 ch
->buffersize
+= len
;
281 if (ch
->tail
&& ch
->tail
->buflen
< BUFFER_GRANULE
) {
282 int copylen
= min(len
, BUFFER_GRANULE
- ch
->tail
->buflen
);
283 memcpy(ch
->tail
->buf
+ ch
->tail
->buflen
, buf
, copylen
);
286 ch
->tail
->buflen
+= copylen
;
289 int grainlen
= min(len
, BUFFER_GRANULE
);
290 struct bufchain_granule
*newbuf
;
291 newbuf
= snew(struct bufchain_granule
);
293 newbuf
->buflen
= grainlen
;
294 memcpy(newbuf
->buf
, buf
, grainlen
);
298 ch
->tail
->next
= newbuf
;
300 ch
->head
= ch
->tail
= newbuf
;
306 void bufchain_consume(bufchain
*ch
, int len
)
308 struct bufchain_granule
*tmp
;
310 assert(ch
->buffersize
>= len
);
313 assert(ch
->head
!= NULL
);
314 if (remlen
>= ch
->head
->buflen
- ch
->head
->bufpos
) {
315 remlen
= ch
->head
->buflen
- ch
->head
->bufpos
;
317 ch
->head
= tmp
->next
;
322 ch
->head
->bufpos
+= remlen
;
323 ch
->buffersize
-= remlen
;
328 void bufchain_prefix(bufchain
*ch
, void **data
, int *len
)
330 *len
= ch
->head
->buflen
- ch
->head
->bufpos
;
331 *data
= ch
->head
->buf
+ ch
->head
->bufpos
;
334 void bufchain_fetch(bufchain
*ch
, void *data
, int len
)
336 struct bufchain_granule
*tmp
;
337 char *data_c
= (char *)data
;
341 assert(ch
->buffersize
>= len
);
346 if (remlen
>= tmp
->buflen
- tmp
->bufpos
)
347 remlen
= tmp
->buflen
- tmp
->bufpos
;
348 memcpy(data_c
, tmp
->buf
+ tmp
->bufpos
, remlen
);
356 /* ----------------------------------------------------------------------
357 * My own versions of malloc, realloc and free. Because I want
358 * malloc and realloc to bomb out and exit the program if they run
359 * out of memory, realloc to reliably call malloc if passed a NULL
360 * pointer, and free to reliably do nothing if passed a NULL
361 * pointer. We can also put trace printouts in, if we need to; and
362 * we can also replace the allocator with an ElectricFence-like
367 void *minefield_c_malloc(size_t size
);
368 void minefield_c_free(void *p
);
369 void *minefield_c_realloc(void *p
, size_t size
);
373 static FILE *fp
= NULL
;
375 static char *mlog_file
= NULL
;
376 static int mlog_line
= 0;
378 void mlog(char *file
, int line
)
383 fp
= fopen("putty_mem.log", "w");
384 setvbuf(fp
, NULL
, _IONBF
, BUFSIZ
);
387 fprintf(fp
, "%s:%d: ", file
, line
);
391 void *safemalloc(size_t size
)
395 p
= minefield_c_malloc(size
);
402 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
403 mlog_file
, mlog_line
, size
);
404 fprintf(fp
, "*** %s\n", str
);
407 strcpy(str
, "Out of memory!");
413 fprintf(fp
, "malloc(%d) returns %p\n", size
, p
);
418 void *saferealloc(void *ptr
, size_t size
)
423 p
= minefield_c_malloc(size
);
429 p
= minefield_c_realloc(ptr
, size
);
431 p
= realloc(ptr
, size
);
437 sprintf(str
, "Out of memory! (%s:%d, size=%d)",
438 mlog_file
, mlog_line
, size
);
439 fprintf(fp
, "*** %s\n", str
);
442 strcpy(str
, "Out of memory!");
448 fprintf(fp
, "realloc(%p,%d) returns %p\n", ptr
, size
, p
);
453 void safefree(void *ptr
)
458 fprintf(fp
, "free(%p)\n", ptr
);
461 minefield_c_free(ptr
);
468 fprintf(fp
, "freeing null pointer - no action taken\n");
472 /* ----------------------------------------------------------------------
473 * Debugging routines.
477 extern void dputs(char *); /* defined in per-platform *misc.c */
479 void debug_printf(char *fmt
, ...)
485 buf
= dupvprintf(fmt
, ap
);
492 void debug_memdump(void *buf
, int len
, int L
)
495 unsigned char *p
= buf
;
499 debug_printf("\t%d (0x%x) bytes:\n", len
, len
);
500 delta
= 15 & (int) p
;
504 for (; 0 < len
; p
+= 16, len
-= 16) {
507 debug_printf("%p: ", p
);
508 strcpy(foo
, "................"); /* sixteen dots */
509 for (i
= 0; i
< 16 && i
< len
; ++i
) {
510 if (&p
[i
] < (unsigned char *) buf
) {
511 dputs(" "); /* 3 spaces */
514 debug_printf("%c%02.2x",
515 &p
[i
] != (unsigned char *) buf
516 && i
% 4 ?
'.' : ' ', p
[i
]
518 if (p
[i
] >= ' ' && p
[i
] <= '~')
519 foo
[i
] = (char) p
[i
];
523 debug_printf("%*s%s\n", (16 - i
) * 3 + 2, "", foo
);
527 #endif /* def DEBUG */