Bug Summary

File:root/firefox-clang/media/ffvpx/libavutil/avsscanf.c
Warning:line 884, column 37
Although the value stored to 'c' is used in the enclosing expression, the value is never actually read from 'c'

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -O2 -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name avsscanf.c -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -ffp-contract=off -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fdebug-compilation-dir=/root/firefox-clang/obj-x86_64-pc-linux-gnu/media/ffvpx/libavutil -fcoverage-compilation-dir=/root/firefox-clang/obj-x86_64-pc-linux-gnu/media/ffvpx/libavutil -resource-dir /usr/lib/llvm-23/lib/clang/23 -include /root/firefox-clang/obj-x86_64-pc-linux-gnu/mozilla-config.h -include libavutil_visibility.h -U _FORTIFY_SOURCE -D _FORTIFY_SOURCE=2 -D DEBUG=1 -D HAVE_AV_CONFIG_H -D ASSERT_LEVEL=2 -I /root/firefox-clang/media/ffvpx/libavutil -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/media/ffvpx/libavutil -I /root/firefox-clang/third_party/khronos/vulkan-headers/include -I /root/firefox-clang/media/mozva -I /root/firefox-clang/media/ffvpx -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include/nspr -I /root/firefox-clang/obj-x86_64-pc-linux-gnu/dist/include/nss -D MOZILLA_CLIENT -internal-isystem /usr/lib/llvm-23/lib/clang/23/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/16/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -Wno-error=tautological-type-limit-compare -Wno-range-loop-analysis -Wno-error=deprecated-declarations -Wno-error=array-bounds -Wno-error=free-nonheap-object -Wno-error=atomic-alignment -Wno-error=deprecated-builtins -Wno-psabi -Wno-error=builtin-macro-redefined -Wno-unknown-warning-option -Wno-character-conversion -Wno-parentheses -Wno-pointer-sign -Wno-sign-compare -Wno-switch -Wno-type-limits -Wno-unused-function -Wno-deprecated-declarations -Wno-absolute-value -Wno-incompatible-pointer-types -Wno-string-conversion -Wno-visibility -ferror-limit 19 -fstrict-flex-arrays=1 -stack-protector 2 -fstack-clash-protection -ftrivial-auto-var-init=pattern -fgnuc-version=4.2.1 -fskip-odr-check-in-gmf -fdiagnostics-absolute-paths -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -mllvm -dwarf-linkage-names=Abstract -faddrsig -fdwarf2-cfi-asm -o /tmp/scan-build-2026-09-01-224014-2642839-1 -x c /root/firefox-clang/media/ffvpx/libavutil/avsscanf.c
1/*
2 * Copyright (c) 2005-2014 Rich Felker, et al.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
18 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
19 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
20 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
21 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
22 */
23
24#include <errno(*__errno_location ()).h>
25#include <limits.h>
26#include <math.h>
27#include <stdarg.h>
28#include <stddef.h>
29#include <stdint.h>
30#include <stdio.h>
31#include <string.h>
32#include <float.h>
33
34#include "avstring.h"
35#include "libm.h"
36
37typedef struct FFFILE {
38 size_t buf_size;
39 unsigned char *buf;
40 unsigned char *rpos, *rend;
41 unsigned char *shend;
42 ptrdiff_t shlim, shcnt;
43 void *cookie;
44 size_t (*read)(struct FFFILE *, unsigned char *, size_t);
45} FFFILE;
46
47#define SIZE_hh-2 -2
48#define SIZE_h-1 -1
49#define SIZE_def0 0
50#define SIZE_l1 1
51#define SIZE_L2 2
52#define SIZE_ll3 3
53
54#define shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf)) ((f)->shcnt + ((f)->rpos - (f)->buf))
55
56static int fftoread(FFFILE *f)
57{
58 f->rpos = f->rend = f->buf + f->buf_size;
59 return 0;
60}
61
62static size_t ffstring_read(FFFILE *f, unsigned char *buf, size_t len)
63{
64 char *src = f->cookie;
65 size_t k = len+256;
66 char *end = memchr(src, 0, k);
67
68 if (end) k = end-src;
69 if (k < len) len = k;
70 memcpy(buf, src, len);
71 f->rpos = (void *)(src+len);
72 f->rend = (void *)(src+k);
73 f->cookie = src+k;
74
75 return len;
76}
77
78static int ffuflow(FFFILE *f)
79{
80 unsigned char c;
81 if (!fftoread(f) && f->read(f, &c, 1)==1) return c;
82 return EOF(-1);
83}
84
85static void ffshlim(FFFILE *f, ptrdiff_t lim)
86{
87 f->shlim = lim;
88 f->shcnt = f->buf - f->rpos;
89 /* If lim is nonzero, rend must be a valid pointer. */
90 if (lim && f->rend - f->rpos > lim)
91 f->shend = f->rpos + lim;
92 else
93 f->shend = f->rend;
94}
95
96static int ffshgetc(FFFILE *f)
97{
98 int c;
99 ptrdiff_t cnt = shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf));
100 if (f->shlim && cnt >= f->shlim || (c=ffuflow(f)) < 0) {
101 f->shcnt = f->buf - f->rpos + cnt;
102 f->shend = 0;
103 return EOF(-1);
104 }
105 cnt++;
106 if (f->shlim && f->rend - f->rpos > f->shlim - cnt)
107 f->shend = f->rpos + (f->shlim - cnt);
108 else
109 f->shend = f->rend;
110 f->shcnt = f->buf - f->rpos + cnt;
111 if (f->rpos[-1] != c) f->rpos[-1] = c;
112 return c;
113}
114
115#define shlim(f, lim)ffshlim((f), (lim)) ffshlim((f), (lim))
116#define shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)) (((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc(f))
117#define shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0) ((f)->shend ? (void)(f)->rpos-- : (void)0)
118
119static const unsigned char table[] = { -1,
120 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
121 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
122 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
123 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,-1,-1,-1,-1,-1,-1,
124 -1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
125 25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
126 -1,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,
127 25,26,27,28,29,30,31,32,33,34,35,-1,-1,-1,-1,-1,
128 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
129 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
130 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
131 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
132 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
133 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
134 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
135 -1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,
136};
137
138static unsigned long long ffintscan(FFFILE *f, unsigned base, int pok, unsigned long long lim)
139{
140 const unsigned char *val = table+1;
141 int c, neg=0;
142 unsigned x;
143 unsigned long long y;
144 if (base > 36 || base == 1) {
145 errno(*__errno_location ()) = EINVAL22;
146 return 0;
147 }
148 while (av_isspace((c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))));
149 if (c=='+' || c=='-') {
150 neg = -(c=='-');
151 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
152 }
153 if ((base == 0 || base == 16) && c=='0') {
154 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
155 if ((c|32)=='x') {
156 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
157 if (val[c]>=16) {
158 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
159 if (pok) shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
160 else shlim(f, 0)ffshlim((f), (0));
161 return 0;
162 }
163 base = 16;
164 } else if (base == 0) {
165 base = 8;
166 }
167 } else {
168 if (base == 0) base = 10;
169 if (val[c] >= base) {
170 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
171 shlim(f, 0)ffshlim((f), (0));
172 errno(*__errno_location ()) = EINVAL22;
173 return 0;
174 }
175 }
176 if (base == 10) {
177 for (x=0; c-'0'<10U && x<=UINT_MAX(2147483647 *2U +1U)/10-1; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
178 x = x*10 + (c-'0');
179 for (y=x; c-'0'<10U && y<=ULLONG_MAX(9223372036854775807LL*2ULL+1ULL)/10 && 10*y<=ULLONG_MAX(9223372036854775807LL*2ULL+1ULL)-(c-'0'); c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
180 y = y*10 + (c-'0');
181 if (c-'0'>=10U) goto done;
182 } else if (!(base & base-1)) {
183 int bs = "\0\1\2\4\7\3\6\5"[(0x17*base)>>5&7];
184 for (x=0; val[c]<base && x<=UINT_MAX(2147483647 *2U +1U)/32; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
185 x = x<<bs | val[c];
186 for (y=x; val[c]<base && y<=ULLONG_MAX(9223372036854775807LL*2ULL+1ULL)>>bs; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
187 y = y<<bs | val[c];
188 } else {
189 for (x=0; val[c]<base && x<=UINT_MAX(2147483647 *2U +1U)/36-1; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
190 x = x*base + val[c];
191 for (y=x; val[c]<base && y<=ULLONG_MAX(9223372036854775807LL*2ULL+1ULL)/base && base*y<=ULLONG_MAX(9223372036854775807LL*2ULL+1ULL)-val[c]; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
192 y = y*base + val[c];
193 }
194 if (val[c]<base) {
195 for (; val[c]<base; c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)));
196 errno(*__errno_location ()) = ERANGE34;
197 y = lim;
198 if (lim&1) neg = 0;
199 }
200done:
201 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
202 if (y>=lim) {
203 if (!(lim&1) && !neg) {
204 errno(*__errno_location ()) = ERANGE34;
205 return lim-1;
206 } else if (y>lim) {
207 errno(*__errno_location ()) = ERANGE34;
208 return lim;
209 }
210 }
211 return (y^neg)-neg;
212}
213
214static long long scanexp(FFFILE *f, int pok)
215{
216 int c;
217 int x;
218 long long y;
219 int neg = 0;
220
221 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
222 if (c=='+' || c=='-') {
223 neg = (c=='-');
224 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
225 if (c-'0'>=10U && pok) shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
226 }
227 if (c-'0'>=10U) {
228 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
229 return LLONG_MIN(-9223372036854775807LL -1LL);
230 }
231 for (x=0; c-'0'<10U && x<INT_MAX2147483647/10; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
232 x = 10*x + (c-'0');
233 for (y=x; c-'0'<10U && y<LLONG_MAX9223372036854775807LL/100; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
234 y = 10*y + (c-'0');
235 for (; c-'0'<10U; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)));
236 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
237 return neg ? -y : y;
238}
239
240#define LD_B1B_DIG2 2
241#define LD_B1B_MAX9007199, 254740991 9007199, 254740991
242#define KMAX128 128
243#define MASK(128 -1) (KMAX128-1)
244
245static double decfloat(FFFILE *f, int c, int bits, int emin, int sign, int pok)
246{
247 uint32_t x[KMAX128];
248 static const uint32_t th[] = { LD_B1B_MAX9007199, 254740991 };
249 int i, j, k, a, z;
250 long long lrp=0, dc=0;
251 long long e10=0;
252 int lnz = 0;
253 int gotdig = 0, gotrad = 0;
254 int rp;
255 int e2;
256 int emax = -emin-bits+3;
257 int denormal = 0;
258 double y;
259 double frac=0;
260 double bias=0;
261 static const int p10s[] = { 10, 100, 1000, 10000,
262 100000, 1000000, 10000000, 100000000 };
263
264 j=0;
265 k=0;
266
267 /* Don't let leading zeros consume buffer space */
268 for (; c=='0'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))) gotdig=1;
269 if (c=='.') {
270 gotrad = 1;
271 for (c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)); c=='0'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))) gotdig=1, lrp--;
272 }
273
274 x[0] = 0;
275 for (; c-'0'<10U || c=='.'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))) {
276 if (c == '.') {
277 if (gotrad) break;
278 gotrad = 1;
279 lrp = dc;
280 } else if (k < KMAX128-3) {
281 dc++;
282 if (c!='0') lnz = dc;
283 if (j) x[k] = x[k]*10 + c-'0';
284 else x[k] = c-'0';
285 if (++j==9) {
286 k++;
287 j=0;
288 }
289 gotdig=1;
290 } else {
291 dc++;
292 if (c!='0') {
293 lnz = (KMAX128-4)*9;
294 x[KMAX128-4] |= 1;
295 }
296 }
297 }
298 if (!gotrad) lrp=dc;
299
300 if (gotdig && (c|32)=='e') {
301 e10 = scanexp(f, pok);
302 if (e10 == LLONG_MIN(-9223372036854775807LL -1LL)) {
303 if (pok) {
304 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
305 } else {
306 shlim(f, 0)ffshlim((f), (0));
307 return 0;
308 }
309 e10 = 0;
310 }
311 lrp += e10;
312 } else if (c>=0) {
313 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
314 }
315 if (!gotdig) {
316 errno(*__errno_location ()) = EINVAL22;
317 shlim(f, 0)ffshlim((f), (0));
318 return 0;
319 }
320
321 /* Handle zero specially to avoid nasty special cases later */
322 if (!x[0]) return sign * 0.0;
323
324 /* Optimize small integers (w/no exponent) and over/under-flow */
325 if (lrp==dc && dc<10 && (bits>30 || x[0]>>bits==0))
326 return sign * (double)x[0];
327 if (lrp > -emin/2) {
328 errno(*__errno_location ()) = ERANGE34;
329 return sign * DBL_MAX1.7976931348623157e+308 * DBL_MAX1.7976931348623157e+308;
330 }
331 if (lrp < emin-2*DBL_MANT_DIG53) {
332 errno(*__errno_location ()) = ERANGE34;
333 return sign * DBL_MIN2.2250738585072014e-308 * DBL_MIN2.2250738585072014e-308;
334 }
335
336 /* Align incomplete final B1B digit */
337 if (j) {
338 for (; j<9; j++) x[k]*=10;
339 k++;
340 j=0;
341 }
342
343 a = 0;
344 z = k;
345 e2 = 0;
346 rp = lrp;
347
348 /* Optimize small to mid-size integers (even in exp. notation) */
349 if (lnz<9 && lnz<=rp && rp < 18) {
350 int bitlim;
351 if (rp == 9) return sign * (double)x[0];
352 if (rp < 9) return sign * (double)x[0] / p10s[8-rp];
353 bitlim = bits-3*(int)(rp-9);
354 if (bitlim>30 || x[0]>>bitlim==0)
355 return sign * (double)x[0] * p10s[rp-10];
356 }
357
358 /* Drop trailing zeros */
359 for (; !x[z-1]; z--);
360
361 /* Align radix point to B1B digit boundary */
362 if (rp % 9) {
363 int rpm9 = rp>=0 ? rp%9 : rp%9+9;
364 int p10 = p10s[8-rpm9];
365 uint32_t carry = 0;
366 for (k=a; k!=z; k++) {
367 uint32_t tmp = x[k] % p10;
368 x[k] = x[k]/p10 + carry;
369 carry = 1000000000/p10 * tmp;
370 if (k==a && !x[k]) {
371 a = (a+1 & MASK(128 -1));
372 rp -= 9;
373 }
374 }
375 if (carry) x[z++] = carry;
376 rp += 9-rpm9;
377 }
378
379 /* Upscale until desired number of bits are left of radix point */
380 while (rp < 9*LD_B1B_DIG2 || (rp == 9*LD_B1B_DIG2 && x[a]<th[0])) {
381 uint32_t carry = 0;
382 e2 -= 29;
383 for (k=(z-1 & MASK(128 -1)); ; k=(k-1 & MASK(128 -1))) {
384 uint64_t tmp = ((uint64_t)x[k] << 29) + carry;
385 if (tmp > 1000000000) {
386 carry = tmp / 1000000000;
387 x[k] = tmp % 1000000000;
388 } else {
389 carry = 0;
390 x[k] = tmp;
391 }
392 if (k==(z-1 & MASK(128 -1)) && k!=a && !x[k]) z = k;
393 if (k==a) break;
394 }
395 if (carry) {
396 rp += 9;
397 a = (a-1 & MASK(128 -1));
398 if (a == z) {
399 z = (z-1 & MASK(128 -1));
400 x[z-1 & MASK(128 -1)] |= x[z];
401 }
402 x[a] = carry;
403 }
404 }
405
406 /* Downscale until exactly number of bits are left of radix point */
407 for (;;) {
408 uint32_t carry = 0;
409 int sh = 1;
410 for (i=0; i<LD_B1B_DIG2; i++) {
411 k = (a+i & MASK(128 -1));
412 if (k == z || x[k] < th[i]) {
413 i=LD_B1B_DIG2;
414 break;
415 }
416 if (x[a+i & MASK(128 -1)] > th[i]) break;
417 }
418 if (i==LD_B1B_DIG2 && rp==9*LD_B1B_DIG2) break;
419 /* FIXME: find a way to compute optimal sh */
420 if (rp > 9+9*LD_B1B_DIG2) sh = 9;
421 e2 += sh;
422 for (k=a; k!=z; k=(k+1 & MASK(128 -1))) {
423 uint32_t tmp = x[k] & (1<<sh)-1;
424 x[k] = (x[k]>>sh) + carry;
425 carry = (1000000000>>sh) * tmp;
426 if (k==a && !x[k]) {
427 a = (a+1 & MASK(128 -1));
428 i--;
429 rp -= 9;
430 }
431 }
432 if (carry) {
433 if ((z+1 & MASK(128 -1)) != a) {
434 x[z] = carry;
435 z = (z+1 & MASK(128 -1));
436 } else x[z-1 & MASK(128 -1)] |= 1;
437 }
438 }
439
440 /* Assemble desired bits into floating point variable */
441 for (y=i=0; i<LD_B1B_DIG2; i++) {
442 if ((a+i & MASK(128 -1))==z) x[(z=(z+1 & MASK(128 -1)))-1] = 0;
443 y = 1000000000.0L * y + x[a+i & MASK(128 -1)];
444 }
445
446 y *= sign;
447
448 /* Limit precision for denormal results */
449 if (bits > DBL_MANT_DIG53+e2-emin) {
450 bits = DBL_MANT_DIG53+e2-emin;
451 if (bits<0) bits=0;
452 denormal = 1;
453 }
454
455 /* Calculate bias term to force rounding, move out lower bits */
456 if (bits < DBL_MANT_DIG53) {
457 bias = copysign(scalbn(1, 2*DBL_MANT_DIG53-bits-1), y);
458 frac = fmod(y, scalbn(1, DBL_MANT_DIG53-bits));
459 y -= frac;
460 y += bias;
461 }
462
463 /* Process tail of decimal input so it can affect rounding */
464 if ((a+i & MASK(128 -1)) != z) {
465 uint32_t t = x[a+i & MASK(128 -1)];
466 if (t < 500000000 && (t || (a+i+1 & MASK(128 -1)) != z))
467 frac += 0.25*sign;
468 else if (t > 500000000)
469 frac += 0.75*sign;
470 else if (t == 500000000) {
471 if ((a+i+1 & MASK(128 -1)) == z)
472 frac += 0.5*sign;
473 else
474 frac += 0.75*sign;
475 }
476 if (DBL_MANT_DIG53-bits >= 2 && !fmod(frac, 1))
477 frac++;
478 }
479
480 y += frac;
481 y -= bias;
482
483 if ((e2+DBL_MANT_DIG53 & INT_MAX2147483647) > emax-5) {
484 if (fabs(y) >= pow(2, DBL_MANT_DIG53)) {
485 if (denormal && bits==DBL_MANT_DIG53+e2-emin)
486 denormal = 0;
487 y *= 0.5;
488 e2++;
489 }
490 if (e2+DBL_MANT_DIG53>emax || (denormal && frac))
491 errno(*__errno_location ()) = ERANGE34;
492 }
493
494 return scalbn(y, e2);
495}
496
497static double hexfloat(FFFILE *f, int bits, int emin, int sign, int pok)
498{
499 uint32_t x = 0;
500 double y = 0;
501 double scale = 1;
502 double bias = 0;
503 int gottail = 0, gotrad = 0, gotdig = 0;
504 long long rp = 0;
505 long long dc = 0;
506 long long e2 = 0;
507 int d;
508 int c;
509
510 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
511
512 /* Skip leading zeros */
513 for (; c=='0'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))
514 gotdig = 1;
515
516 if (c=='.') {
517 gotrad = 1;
518 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
519 /* Count zeros after the radix point before significand */
520 for (rp=0; c=='0'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)), rp--) gotdig = 1;
521 }
522
523 for (; c-'0'<10U || (c|32)-'a'<6U || c=='.'; c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))) {
524 if (c=='.') {
525 if (gotrad) break;
526 rp = dc;
527 gotrad = 1;
528 } else {
529 gotdig = 1;
530 if (c > '9') d = (c|32)+10-'a';
531 else d = c-'0';
532 if (dc<8) {
533 x = x*16 + d;
534 } else if (dc < DBL_MANT_DIG53/4+1) {
535 y += d*(scale/=16);
536 } else if (d && !gottail) {
537 y += 0.5*scale;
538 gottail = 1;
539 }
540 dc++;
541 }
542 }
543 if (!gotdig) {
544 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
545 if (pok) {
546 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
547 if (gotrad) shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
548 } else {
549 shlim(f, 0)ffshlim((f), (0));
550 }
551 return sign * 0.0;
552 }
553 if (!gotrad) rp = dc;
554 while (dc<8) x *= 16, dc++;
555 if ((c|32)=='p') {
556 e2 = scanexp(f, pok);
557 if (e2 == LLONG_MIN(-9223372036854775807LL -1LL)) {
558 if (pok) {
559 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
560 } else {
561 shlim(f, 0)ffshlim((f), (0));
562 return 0;
563 }
564 e2 = 0;
565 }
566 } else {
567 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
568 }
569 e2 += 4*rp - 32;
570
571 if (!x) return sign * 0.0;
572 if (e2 > -emin) {
573 errno(*__errno_location ()) = ERANGE34;
574 return sign * DBL_MAX1.7976931348623157e+308 * DBL_MAX1.7976931348623157e+308;
575 }
576 if (e2 < emin-2*DBL_MANT_DIG53) {
577 errno(*__errno_location ()) = ERANGE34;
578 return sign * DBL_MIN2.2250738585072014e-308 * DBL_MIN2.2250738585072014e-308;
579 }
580
581 while (x < 0x80000000) {
582 if (y>=0.5) {
583 x += x + 1;
584 y += y - 1;
585 } else {
586 x += x;
587 y += y;
588 }
589 e2--;
590 }
591
592 if (bits > 32+e2-emin) {
593 bits = 32+e2-emin;
594 if (bits<0) bits=0;
595 }
596
597 if (bits < DBL_MANT_DIG53)
598 bias = copysign(scalbn(1, 32+DBL_MANT_DIG53-bits-1), sign);
599
600 if (bits<32 && y && !(x&1)) x++, y=0;
601
602 y = bias + sign*(double)x + sign*y;
603 y -= bias;
604
605 if (!y) errno(*__errno_location ()) = ERANGE34;
606
607 return scalbn(y, e2);
608}
609
610static double fffloatscan(FFFILE *f, int prec, int pok)
611{
612 int sign = 1;
613 size_t i;
614 int bits;
615 int emin;
616 int c;
617
618 switch (prec) {
619 case 0:
620 bits = FLT_MANT_DIG24;
621 emin = FLT_MIN_EXP(-125)-bits;
622 break;
623 case 1:
624 bits = DBL_MANT_DIG53;
625 emin = DBL_MIN_EXP(-1021)-bits;
626 break;
627 case 2:
628 bits = DBL_MANT_DIG53;
629 emin = DBL_MIN_EXP(-1021)-bits;
630 break;
631 default:
632 return 0;
633 }
634
635 while (av_isspace((c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))));
636
637 if (c=='+' || c=='-') {
638 sign -= 2*(c=='-');
639 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
640 }
641
642 for (i=0; i<8 && (c|32)=="infinity"[i]; i++)
643 if (i<7) c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
644 if (i==3 || i==8 || (i>3 && pok)) {
645 if (i!=8) {
646 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
647 if (pok) for (; i>3; i--) shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
648 }
649 return sign * INFINITY(__builtin_inff());
650 }
651 if (!i) for (i=0; i<3 && (c|32)=="nan"[i]; i++)
652 if (i<2) c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
653 if (i==3) {
654 if (shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)) != '(') {
655 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
656 return NAN(__builtin_nanf(""));
657 }
658 for (i=1; ; i++) {
659 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
660 if (c-'0'<10U || c-'A'<26U || c-'a'<26U || c=='_')
661 continue;
662 if (c==')') return NAN(__builtin_nanf(""));
663 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
664 if (!pok) {
665 errno(*__errno_location ()) = EINVAL22;
666 shlim(f, 0)ffshlim((f), (0));
667 return 0;
668 }
669 while (i--) shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
670 return NAN(__builtin_nanf(""));
671 }
672 }
673
674 if (i) {
675 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
676 errno(*__errno_location ()) = EINVAL22;
677 shlim(f, 0)ffshlim((f), (0));
678 return 0;
679 }
680
681 if (c=='0') {
682 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
683 if ((c|32) == 'x')
684 return hexfloat(f, bits, emin, sign, pok);
685 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
686 c = '0';
687 }
688
689 return decfloat(f, c, bits, emin, sign, pok);
690}
691
692static void *arg_n(va_list ap, unsigned int n)
693{
694 void *p;
695 unsigned int i;
696 va_list ap2;
697 va_copy(ap2, ap)__builtin_va_copy(ap2, ap);
698 for (i=n; i>1; i--) va_arg(ap2, void *)__builtin_va_arg(ap2, void *);
699 p = va_arg(ap2, void *)__builtin_va_arg(ap2, void *);
700 va_end(ap2)__builtin_va_end(ap2);
701 return p;
702}
703
704static void store_int(void *dest, int size, unsigned long long i)
705{
706 if (!dest) return;
707 switch (size) {
708 case SIZE_hh-2:
709 *(char *)dest = i;
710 break;
711 case SIZE_h-1:
712 *(short *)dest = i;
713 break;
714 case SIZE_def0:
715 *(int *)dest = i;
716 break;
717 case SIZE_l1:
718 *(long *)dest = i;
719 break;
720 case SIZE_ll3:
721 *(long long *)dest = i;
722 break;
723 }
724}
725
726static int ff_vfscanf(FFFILE *f, const char *fmt, va_list ap)
727{
728 int width;
729 int size;
730 int base;
731 const unsigned char *p;
732 int c, t;
733 char *s;
734 void *dest=NULL((void*)0);
735 int invert;
736 int matches=0;
737 unsigned long long x;
738 double y;
739 ptrdiff_t pos = 0;
740 unsigned char scanset[257];
741 size_t i;
742
743 for (p=(const unsigned char *)fmt; *p; p++) {
744
745 if (av_isspace(*p)) {
746 while (av_isspace(p[1])) p++;
747 shlim(f, 0)ffshlim((f), (0));
748 while (av_isspace(shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))));
749 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
750 pos += shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf));
751 continue;
752 }
753 if (*p != '%' || p[1] == '%') {
754 shlim(f, 0)ffshlim((f), (0));
755 if (*p == '%') {
756 p++;
757 while (av_isspace((c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))));
758 } else {
759 c = shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f));
760 }
761 if (c!=*p) {
762 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
763 if (c<0) goto input_fail;
764 goto match_fail;
765 }
766 pos += shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf));
767 continue;
768 }
769
770 p++;
771 if (*p=='*') {
772 dest = 0; p++;
773 } else if (av_isdigit(*p) && p[1]=='$') {
774 dest = arg_n(ap, *p-'0'); p+=2;
775 } else {
776 dest = va_arg(ap, void *)__builtin_va_arg(ap, void *);
777 }
778
779 for (width=0; av_isdigit(*p); p++) {
780 width = 10*width + *p - '0';
781 }
782
783 if (*p=='m') {
784 s = 0;
785 p++;
786 }
787
788 size = SIZE_def0;
789 switch (*p++) {
790 case 'h':
791 if (*p == 'h') p++, size = SIZE_hh-2;
792 else size = SIZE_h-1;
793 break;
794 case 'l':
795 if (*p == 'l') p++, size = SIZE_ll3;
796 else size = SIZE_l1;
797 break;
798 case 'j':
799 size = SIZE_ll3;
800 break;
801 case 'z':
802 case 't':
803 size = SIZE_l1;
804 break;
805 case 'L':
806 size = SIZE_L2;
807 break;
808 case 'd': case 'i': case 'o': case 'u': case 'x':
809 case 'a': case 'e': case 'f': case 'g':
810 case 'A': case 'E': case 'F': case 'G': case 'X':
811 case 's': case 'c': case '[':
812 case 'S': case 'C':
813 case 'p': case 'n':
814 p--;
815 break;
816 default:
817 goto fmt_fail;
818 }
819
820 t = *p;
821
822 /* C or S */
823 if ((t&0x2f) == 3) {
824 t |= 32;
825 size = SIZE_l1;
826 }
827
828 switch (t) {
829 case 'c':
830 if (width < 1) width = 1;
831 case '[':
832 break;
833 case 'n':
834 store_int(dest, size, pos);
835 /* do not increment match count, etc! */
836 continue;
837 default:
838 shlim(f, 0)ffshlim((f), (0));
839 while (av_isspace(shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f))));
840 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
841 pos += shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf));
842 }
843
844 shlim(f, width)ffshlim((f), (width));
845 if (shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)) < 0) goto input_fail;
846 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
847
848 switch (t) {
849 case 's':
850 case 'c':
851 case '[':
852 if (t == 'c' || t == 's') {
853 memset(scanset, -1, sizeof scanset);
854 scanset[0] = 0;
855 if (t == 's') {
856 scanset[1 + '\t'] = 0;
857 scanset[1 + '\n'] = 0;
858 scanset[1 + '\v'] = 0;
859 scanset[1 + '\f'] = 0;
860 scanset[1 + '\r'] = 0;
861 scanset[1 + ' ' ] = 0;
862 }
863 } else {
864 if (*++p == '^') p++, invert = 1;
865 else invert = 0;
866 memset(scanset, invert, sizeof scanset);
867 scanset[0] = 0;
868 if (*p == '-') p++, scanset[1+'-'] = 1-invert;
869 else if (*p == ']') p++, scanset[1+']'] = 1-invert;
870 for (; *p != ']'; p++) {
871 if (!*p) goto fmt_fail;
872 if (*p=='-' && p[1] && p[1] != ']')
873 for (c=p++[-1]; c<*p; c++)
874 scanset[1+c] = 1-invert;
875 scanset[1+*p] = 1-invert;
876 }
877 }
878 s = 0;
879 i = 0;
880 if ((s = dest)) {
881 while (scanset[(c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))+1])
882 s[i++] = c;
883 } else {
884 while (scanset[(c=shgetc(f)(((f)->rpos < (f)->shend) ? *(f)->rpos++ : ffshgetc
(f)))+1]);
Although the value stored to 'c' is used in the enclosing expression, the value is never actually read from 'c'
885 }
886 shunget(f)((f)->shend ? (void)(f)->rpos-- : (void)0);
887 if (!shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf))) goto match_fail;
888 if (t == 'c' && shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf)) != width) goto match_fail;
889 if (t != 'c') {
890 if (s) s[i] = 0;
891 }
892 break;
893 case 'p':
894 case 'X':
895 case 'x':
896 base = 16;
897 goto int_common;
898 case 'o':
899 base = 8;
900 goto int_common;
901 case 'd':
902 case 'u':
903 base = 10;
904 goto int_common;
905 case 'i':
906 base = 0;
907int_common:
908 x = ffintscan(f, base, 0, ULLONG_MAX(9223372036854775807LL*2ULL+1ULL));
909 if (!shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf)))
910 goto match_fail;
911 if (t=='p' && dest)
912 *(void **)dest = (void *)(uintptr_t)x;
913 else
914 store_int(dest, size, x);
915 break;
916 case 'a': case 'A':
917 case 'e': case 'E':
918 case 'f': case 'F':
919 case 'g': case 'G':
920 y = fffloatscan(f, size, 0);
921 if (!shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf)))
922 goto match_fail;
923 if (dest) {
924 switch (size) {
925 case SIZE_def0:
926 *(float *)dest = y;
927 break;
928 case SIZE_l1:
929 *(double *)dest = y;
930 break;
931 case SIZE_L2:
932 *(double *)dest = y;
933 break;
934 }
935 }
936 break;
937 }
938
939 pos += shcnt(f)((f)->shcnt + ((f)->rpos - (f)->buf));
940 if (dest) matches++;
941 }
942 if (0) {
943fmt_fail:
944input_fail:
945 if (!matches) matches--;
946 }
947match_fail:
948 return matches;
949}
950
951static int ff_vsscanf(const char *s, const char *fmt, va_list ap)
952{
953 FFFILE f = {
954 .buf = (void *)s, .cookie = (void *)s,
955 .read = ffstring_read,
956 };
957
958 return ff_vfscanf(&f, fmt, ap);
959}
960
961int av_sscanf(const char *string, const char *format, ...)
962{
963 int ret;
964 va_list ap;
965 va_start(ap, format)__builtin_va_start(ap, format);
966 ret = ff_vsscanf(string, format, ap);
967 va_end(ap)__builtin_va_end(ap);
968 return ret;
969}