summaryrefslogtreecommitdiffstats
path: root/misc/bstr.c
blob: bb8446d254d16ed202651f67c15d0b39dadf53cf (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
/*
 * This file is part of MPlayer.
 *
 * MPlayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * MPlayer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <string.h>
#include <strings.h>
#include <assert.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdlib.h>

#include <libavutil/common.h>

#include "talloc.h"

#include "common/common.h"
#include "misc/ctype.h"
#include "bstr.h"

int bstrcmp(struct bstr str1, struct bstr str2)
{
    int ret = 0;
    if (str1.len && str2.len)
        ret = memcmp(str1.start, str2.start, FFMIN(str1.len, str2.len));

    if (!ret) {
        if (str1.len == str2.len)
            return 0;
        else if (str1.len > str2.len)
            return 1;
        else
            return -1;
    }
    return ret;
}

int bstrcasecmp(struct bstr str1, struct bstr str2)
{
    int ret = 0;
    if (str1.len && str2.len)
        ret = strncasecmp(str1.start, str2.start, FFMIN(str1.len, str2.len));

    if (!ret) {
        if (str1.len == str2.len)
            return 0;
        else if (str1.len > str2.len)
            return 1;
        else
            return -1;
    }
    return ret;
}

int bstrchr(struct bstr str, int c)
{
    for (int i = 0; i < str.len; i++)
        if (str.start[i] == c)
            return i;
    return -1;
}

int bstrrchr(struct bstr str, int c)
{
    for (int i = str.len - 1; i >= 0; i--)
        if (str.start[i] == c)
            return i;
    return -1;
}

int bstrcspn(struct bstr str, const char *reject)
{
    int i;
    for (i = 0; i < str.len; i++)
        if (strchr(reject, str.start[i]))
            break;
    return i;
}

int bstrspn(struct bstr str, const char *accept)
{
    int i;
    for (i = 0; i < str.len; i++)
        if (!strchr(accept, str.start[i]))
            break;
    return i;
}

int bstr_find(struct bstr haystack, struct bstr needle)
{
    for (int i = 0; i < haystack.len; i++)
        if (bstr_startswith(bstr_splice(haystack, i, haystack.len), needle))
            return i;
    return -1;
}

struct bstr bstr_lstrip(struct bstr str)
{
    while (str.len && mp_isspace(*str.start)) {
        str.start++;
        str.len--;
    }
    return str;
}

struct bstr bstr_strip(struct bstr str)
{
    str = bstr_lstrip(str);
    while (str.len && mp_isspace(str.start[str.len - 1]))
        str.len--;
    return str;
}

struct bstr bstr_split(struct bstr str, const char *sep, struct bstr *rest)
{
    int start;
    for (start = 0; start < str.len; start++)
        if (!strchr(sep, str.start[start]))
            break;
    str = bstr_cut(str, start);
    int end = bstrcspn(str, sep);
    if (rest) {
        *rest = bstr_cut(str, end);
    }
    return bstr_splice(str, 0, end);
}

// Unlike with bstr_split(), tok is a string, and not a set of char.
// If tok is in str, return true, and: concat(out_left, tok, out_right) == str
// Otherwise, return false, and set out_left==str, out_right==""
bool bstr_split_tok(bstr str, const char *tok, bstr *out_left, bstr *out_right)
{
    bstr bsep = bstr0(tok);
    int pos = bstr_find(str, bsep);
    if (pos < 0)
        pos = str.len;
    *out_left = bstr_splice(str, 0, pos);
    *out_right = bstr_cut(str, pos + bsep.len);
    return pos != str.len;
}

struct bstr bstr_splice(struct bstr str, int start, int end)
{
    if (start < 0)
        start += str.len;
    if (end < 0)
        end += str.len;
    end = FFMIN(end, str.len);
    start = FFMAX(start, 0);
    end = FFMAX(end, start);
    str.start += start;
    str.len = end - start;
    return str;
}

long long bstrtoll(struct bstr str, struct bstr *rest, int base)
{
    str = bstr_lstrip(str);
    char buf[51];
    int len = FFMIN(str.len, 50);
    memcpy(buf, str.start, len);
    buf[len] = 0;
    char *endptr;
    long long r = strtoll(buf, &endptr, base);
    if (rest)
        *rest = bstr_cut(str, endptr - buf);
    return r;
}

double bstrtod(struct bstr str, struct bstr *rest)
{
    str = bstr_lstrip(str);
    char buf[101];
    int len = FFMIN(str.len, 100);
    memcpy(buf, str.start, len);
    buf[len] = 0;
    char *endptr;
    double r = strtod(buf, &endptr);
    if (rest)
        *rest = bstr_cut(str, endptr - buf);
    return r;
}

struct bstr *bstr_splitlines(void *talloc_ctx, struct bstr str)
{
    if (str.len == 0)
        return NULL;
    int count = 0;
    for (int i = 0; i < str.len; i++)
        if (str.start[i] == '\n')
            count++;
    if (str.start[str.len - 1] != '\n')
        count++;
    struct bstr *r = talloc_array_ptrtype(talloc_ctx, r, count);
    unsigned char *p = str.start;
    for (int i = 0; i < count - 1; i++) {
        r[i].start = p;
        while (*p++ != '\n');
        r[i].len = p - r[i].start;
    }
    r[count - 1].start = p;
    r[count - 1].len = str.start + str.len - p;
    return r;
}

struct bstr bstr_getline(struct bstr str, struct bstr *rest)
{
    int pos = bstrchr(str, '\n');
    if (pos < 0)
        pos = str.len;
    if (rest)
        *rest = bstr_cut(str, pos + 1);
    return bstr_splice(str, 0, pos + 1);
}

struct bstr bstr_strip_linebreaks(struct bstr str)
{
    if (bstr_endswith0(str, "\r\n")) {
        str = bstr_splice(str, 0, str.len - 2);
    } else if (bstr_endswith0(str, "\n")) {
        str = bstr_splice(str, 0, str.len - 1);
    }
    return str;
}

bool bstr_eatstart(struct bstr *s, struct bstr prefix)
{
    if (!bstr_startswith(*s, prefix))
        return false;
    *s = bstr_cut(*s, prefix.len);
    return true;
}

void bstr_lower(struct bstr str)
{
    for (int i = 0; i < str.len; i++)
        str.start[i] = mp_tolower(str.start[i]);
}

int bstr_sscanf(struct bstr str, const char *format, ...)
{
    char *ptr = bstrdup0(NULL, str);
    va_list va;
    va_start(va, format);
    int ret = vsscanf(ptr, format, va);
    va_end(va);
    talloc_free(ptr);
    return ret;
}

int bstr_parse_utf8_code_length(unsigned char b)
{
    if (b < 128)
        return 1;
    int bytes = 7 - av_log2(b ^ 255);
    return (bytes >= 2 && bytes <= 4) ? bytes : -1;
}

int bstr_decode_utf8(struct bstr s, struct bstr *out_next)
{
    if (s.len == 0)
        return -1;
    unsigned int codepoint = s.start[0];
    s.start++; s.len--;
    if (codepoint >= 128) {
        int bytes = bstr_parse_utf8_code_length(codepoint);
        if (bytes < 1 || s.len < bytes - 1)
            return -1;
        codepoint &= 127 >> bytes;
        for (int n = 1; n < bytes; n++) {
            int tmp = (unsigned char)s.start[0];
            if ((tmp & 0xC0) != 0x80)
                return -1;
            codepoint = (codepoint << 6) | (tmp & ~0xC0);
            s.start++; s.len--;
        }
        if (codepoint > 0x10FFFF || (codepoint >= 0xD800 && codepoint <= 0xDFFF))
            return -1;
        // Overlong sequences - check taken from libavcodec.
        // (The only reason we even bother with this is to make libavcodec's
        //  retarded subtitle utf-8 check happy.)
        unsigned int min = bytes == 2 ? 0x80 : 1 << (5 * bytes - 4);
        if (codepoint < min)
            return -1;
    }
    if (out_next)
        *out_next = s;
    return codepoint;
}

struct bstr bstr_split_utf8(struct bstr str, struct bstr *out_next)
{
    bstr rest;
    int code = bstr_decode_utf8(str, &rest);
    if (code < 0)
        return (bstr){0};
    if (out_next)
        *out_next = rest;
    return bstr_splice(str, 0, str.len - rest.len);
}

int bstr_validate_utf8(struct bstr s)
{
    while (s.len) {
        if (bstr_decode_utf8(s, &s) < 0) {
            // Try to guess whether the sequence was just cut-off.
            unsigned int codepoint = (unsigned char)s.start[0];
            int bytes = bstr_parse_utf8_code_length(codepoint);
            if (bytes > 1 && s.len < 6) {
                // Manually check validity of left bytes
                for (int n = 1; n < bytes; n++) {
                    if (n >= s.len) {
                        // Everything valid until now - just cut off.
                        return -(bytes - s.len);
                    }
                    int tmp = (unsigned char)s.start[n];
                    if ((tmp & 0xC0) != 0x80)
                        break;
                }
            }
            return -8;
        }
    }
    return 0;
}

struct bstr bstr_sanitize_utf8_latin1(void *talloc_ctx, struct bstr s)
{
    bstr new = {0};
    bstr left = s;
    unsigned char *first_ok = s.start;
    while (left.len) {
        int r = bstr_decode_utf8(left, &left);
        if (r < 0) {
            bstr_xappend(talloc_ctx, &new, (bstr){first_ok, left.start - first_ok});
            mp_append_utf8_bstr(talloc_ctx, &new, (unsigned char)left.start[0]);
            left.start += 1;
            left.len -= 1;
            first_ok = left.start;
        }
    }
    if (!new.start)
        return s;
    if (first_ok != left.start)
        bstr_xappend(talloc_ctx, &new, (bstr){first_ok, left.start - first_ok});
    return new;
}

static void resize_append(void *talloc_ctx, bstr *s, size_t append_min)
{
    size_t size = talloc_get_size(s->start);
    assert(s->len <= size);
    if (append_min > size - s->len) {
        if (append_min < size)
            append_min = size; // preallocate in power of 2s
        if (size >= SIZE_MAX / 2 || append_min >= SIZE_MAX / 2)
            abort(); // oom
        s->start = talloc_realloc_size(talloc_ctx, s->start, size + append_min);
    }
}

// Append the string, so that *s = *s + append. s->start is expected to be
// a talloc allocation (which can be realloced) or NULL.
// This function will always implicitly append a \0 after the new string for
// convenience.
// talloc_ctx will be used as parent context, if s->start is NULL.
void bstr_xappend(void *talloc_ctx, bstr *s, bstr append)
{
    if (!append.len)
        return;
    resize_append(talloc_ctx, s, append.len + 1);
    memcpy(s->start + s->len, append.start, append.len);
    s->len += append.len;
    s->start[s->len] = '\0';
}

void bstr_xappend_asprintf(void *talloc_ctx, bstr *s, const char *fmt, ...)
{
    va_list ap;
    va_start(ap, fmt);
    bstr_xappend_vasprintf(talloc_ctx, s, fmt, ap);
    va_end(ap);
}

// Exactly as bstr_xappend(), but with a formatted string.
void bstr_xappend_vasprintf(void *talloc_ctx, bstr *s, const char *fmt,
                            va_list ap)
{
    int size;
    va_list copy;
    va_copy(copy, ap);
    char c;
    size = vsnprintf(&c, 1, fmt, copy);
    va_end(copy);

    if (size < 0)
        abort();

    resize_append(talloc_ctx, s, size + 1);
    vsnprintf(s->start + s->len, size + 1, fmt, ap);
    s->len += size;
}

bool bstr_case_startswith(struct bstr s, struct bstr prefix)
{
    struct bstr start = bstr_splice(s, 0, prefix.len);
    return start.len == prefix.len && bstrcasecmp(start, prefix) == 0;
}

bool bstr_case_endswith(struct bstr s, struct bstr suffix)
{
    struct bstr end = bstr_cut(s, -suffix.len);
    return end.len == suffix.len && bstrcasecmp(end, suffix) == 0;
}

struct bstr bstr_strip_ext(struct bstr str)
{
    int dotpos = bstrrchr(str, '.');
    if (dotpos < 0)
        return str;
    return (struct bstr){str.start, dotpos};
}

struct bstr bstr_get_ext(struct bstr s)
{
    int dotpos = bstrrchr(s, '.');
    if (dotpos < 0)
        return (struct bstr){NULL, 0};
    return bstr_splice(s, dotpos + 1, s.len);
}