PostgreSQL Source Code  git master
utilities.c
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1 #include "header.h"
2 
3 #define CREATE_SIZE 1
4 
5 extern symbol * create_s(void) {
6  symbol * p;
7  void * mem = malloc(HEAD + (CREATE_SIZE + 1) * sizeof(symbol));
8  if (mem == NULL) return NULL;
9  p = (symbol *) (HEAD + (char *) mem);
10  CAPACITY(p) = CREATE_SIZE;
11  SET_SIZE(p, 0);
12  return p;
13 }
14 
15 extern void lose_s(symbol * p) {
16  if (p == NULL) return;
17  free((char *) p - HEAD);
18 }
19 
20 /*
21  new_p = skip_utf8(p, c, l, n); skips n characters forwards from p + c.
22  new_p is the new position, or -1 on failure.
23 
24  -- used to implement hop and next in the utf8 case.
25 */
26 
27 extern int skip_utf8(const symbol * p, int c, int limit, int n) {
28  int b;
29  if (n < 0) return -1;
30  for (; n > 0; n--) {
31  if (c >= limit) return -1;
32  b = p[c++];
33  if (b >= 0xC0) { /* 1100 0000 */
34  while (c < limit) {
35  b = p[c];
36  if (b >= 0xC0 || b < 0x80) break;
37  /* break unless b is 10------ */
38  c++;
39  }
40  }
41  }
42  return c;
43 }
44 
45 /*
46  new_p = skip_b_utf8(p, c, lb, n); skips n characters backwards from p + c - 1
47  new_p is the new position, or -1 on failure.
48 
49  -- used to implement hop and next in the utf8 case.
50 */
51 
52 extern int skip_b_utf8(const symbol * p, int c, int limit, int n) {
53  int b;
54  if (n < 0) return -1;
55  for (; n > 0; n--) {
56  if (c <= limit) return -1;
57  b = p[--c];
58  if (b >= 0x80) { /* 1000 0000 */
59  while (c > limit) {
60  b = p[c];
61  if (b >= 0xC0) break; /* 1100 0000 */
62  c--;
63  }
64  }
65  }
66  return c;
67 }
68 
69 /* Code for character groupings: utf8 cases */
70 
71 static int get_utf8(const symbol * p, int c, int l, int * slot) {
72  int b0, b1, b2;
73  if (c >= l) return 0;
74  b0 = p[c++];
75  if (b0 < 0xC0 || c == l) { /* 1100 0000 */
76  *slot = b0;
77  return 1;
78  }
79  b1 = p[c++] & 0x3F;
80  if (b0 < 0xE0 || c == l) { /* 1110 0000 */
81  *slot = (b0 & 0x1F) << 6 | b1;
82  return 2;
83  }
84  b2 = p[c++] & 0x3F;
85  if (b0 < 0xF0 || c == l) { /* 1111 0000 */
86  *slot = (b0 & 0xF) << 12 | b1 << 6 | b2;
87  return 3;
88  }
89  *slot = (b0 & 0x7) << 18 | b1 << 12 | b2 << 6 | (p[c] & 0x3F);
90  return 4;
91 }
92 
93 static int get_b_utf8(const symbol * p, int c, int lb, int * slot) {
94  int a, b;
95  if (c <= lb) return 0;
96  b = p[--c];
97  if (b < 0x80 || c == lb) { /* 1000 0000 */
98  *slot = b;
99  return 1;
100  }
101  a = b & 0x3F;
102  b = p[--c];
103  if (b >= 0xC0 || c == lb) { /* 1100 0000 */
104  *slot = (b & 0x1F) << 6 | a;
105  return 2;
106  }
107  a |= (b & 0x3F) << 6;
108  b = p[--c];
109  if (b >= 0xE0 || c == lb) { /* 1110 0000 */
110  *slot = (b & 0xF) << 12 | a;
111  return 3;
112  }
113  *slot = (p[--c] & 0x7) << 18 | (b & 0x3F) << 12 | a;
114  return 4;
115 }
116 
117 extern int in_grouping_U(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
118  do {
119  int ch;
120  int w = get_utf8(z->p, z->c, z->l, & ch);
121  if (!w) return -1;
122  if (ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0)
123  return w;
124  z->c += w;
125  } while (repeat);
126  return 0;
127 }
128 
129 extern int in_grouping_b_U(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
130  do {
131  int ch;
132  int w = get_b_utf8(z->p, z->c, z->lb, & ch);
133  if (!w) return -1;
134  if (ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0)
135  return w;
136  z->c -= w;
137  } while (repeat);
138  return 0;
139 }
140 
141 extern int out_grouping_U(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
142  do {
143  int ch;
144  int w = get_utf8(z->p, z->c, z->l, & ch);
145  if (!w) return -1;
146  if (!(ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0))
147  return w;
148  z->c += w;
149  } while (repeat);
150  return 0;
151 }
152 
153 extern int out_grouping_b_U(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
154  do {
155  int ch;
156  int w = get_b_utf8(z->p, z->c, z->lb, & ch);
157  if (!w) return -1;
158  if (!(ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0))
159  return w;
160  z->c -= w;
161  } while (repeat);
162  return 0;
163 }
164 
165 /* Code for character groupings: non-utf8 cases */
166 
167 extern int in_grouping(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
168  do {
169  int ch;
170  if (z->c >= z->l) return -1;
171  ch = z->p[z->c];
172  if (ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0)
173  return 1;
174  z->c++;
175  } while (repeat);
176  return 0;
177 }
178 
179 extern int in_grouping_b(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
180  do {
181  int ch;
182  if (z->c <= z->lb) return -1;
183  ch = z->p[z->c - 1];
184  if (ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0)
185  return 1;
186  z->c--;
187  } while (repeat);
188  return 0;
189 }
190 
191 extern int out_grouping(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
192  do {
193  int ch;
194  if (z->c >= z->l) return -1;
195  ch = z->p[z->c];
196  if (!(ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0))
197  return 1;
198  z->c++;
199  } while (repeat);
200  return 0;
201 }
202 
203 extern int out_grouping_b(struct SN_env * z, const unsigned char * s, int min, int max, int repeat) {
204  do {
205  int ch;
206  if (z->c <= z->lb) return -1;
207  ch = z->p[z->c - 1];
208  if (!(ch > max || (ch -= min) < 0 || (s[ch >> 3] & (0X1 << (ch & 0X7))) == 0))
209  return 1;
210  z->c--;
211  } while (repeat);
212  return 0;
213 }
214 
215 extern int eq_s(struct SN_env * z, int s_size, const symbol * s) {
216  if (z->l - z->c < s_size || memcmp(z->p + z->c, s, s_size * sizeof(symbol)) != 0) return 0;
217  z->c += s_size; return 1;
218 }
219 
220 extern int eq_s_b(struct SN_env * z, int s_size, const symbol * s) {
221  if (z->c - z->lb < s_size || memcmp(z->p + z->c - s_size, s, s_size * sizeof(symbol)) != 0) return 0;
222  z->c -= s_size; return 1;
223 }
224 
225 extern int eq_v(struct SN_env * z, const symbol * p) {
226  return eq_s(z, SIZE(p), p);
227 }
228 
229 extern int eq_v_b(struct SN_env * z, const symbol * p) {
230  return eq_s_b(z, SIZE(p), p);
231 }
232 
233 extern int find_among(struct SN_env * z, const struct among * v, int v_size) {
234 
235  int i = 0;
236  int j = v_size;
237 
238  int c = z->c; int l = z->l;
239  const symbol * q = z->p + c;
240 
241  const struct among * w;
242 
243  int common_i = 0;
244  int common_j = 0;
245 
246  int first_key_inspected = 0;
247 
248  while (1) {
249  int k = i + ((j - i) >> 1);
250  int diff = 0;
251  int common = common_i < common_j ? common_i : common_j; /* smaller */
252  w = v + k;
253  {
254  int i2; for (i2 = common; i2 < w->s_size; i2++) {
255  if (c + common == l) { diff = -1; break; }
256  diff = q[common] - w->s[i2];
257  if (diff != 0) break;
258  common++;
259  }
260  }
261  if (diff < 0) {
262  j = k;
263  common_j = common;
264  } else {
265  i = k;
266  common_i = common;
267  }
268  if (j - i <= 1) {
269  if (i > 0) break; /* v->s has been inspected */
270  if (j == i) break; /* only one item in v */
271 
272  /* - but now we need to go round once more to get
273  v->s inspected. This looks messy, but is actually
274  the optimal approach. */
275 
276  if (first_key_inspected) break;
277  first_key_inspected = 1;
278  }
279  }
280  while (1) {
281  w = v + i;
282  if (common_i >= w->s_size) {
283  z->c = c + w->s_size;
284  if (w->function == 0) return w->result;
285  {
286  int res = w->function(z);
287  z->c = c + w->s_size;
288  if (res) return w->result;
289  }
290  }
291  i = w->substring_i;
292  if (i < 0) return 0;
293  }
294 }
295 
296 /* find_among_b is for backwards processing. Same comments apply */
297 
298 extern int find_among_b(struct SN_env * z, const struct among * v, int v_size) {
299 
300  int i = 0;
301  int j = v_size;
302 
303  int c = z->c; int lb = z->lb;
304  const symbol * q = z->p + c - 1;
305 
306  const struct among * w;
307 
308  int common_i = 0;
309  int common_j = 0;
310 
311  int first_key_inspected = 0;
312 
313  while (1) {
314  int k = i + ((j - i) >> 1);
315  int diff = 0;
316  int common = common_i < common_j ? common_i : common_j;
317  w = v + k;
318  {
319  int i2; for (i2 = w->s_size - 1 - common; i2 >= 0; i2--) {
320  if (c - common == lb) { diff = -1; break; }
321  diff = q[- common] - w->s[i2];
322  if (diff != 0) break;
323  common++;
324  }
325  }
326  if (diff < 0) { j = k; common_j = common; }
327  else { i = k; common_i = common; }
328  if (j - i <= 1) {
329  if (i > 0) break;
330  if (j == i) break;
331  if (first_key_inspected) break;
332  first_key_inspected = 1;
333  }
334  }
335  while (1) {
336  w = v + i;
337  if (common_i >= w->s_size) {
338  z->c = c - w->s_size;
339  if (w->function == 0) return w->result;
340  {
341  int res = w->function(z);
342  z->c = c - w->s_size;
343  if (res) return w->result;
344  }
345  }
346  i = w->substring_i;
347  if (i < 0) return 0;
348  }
349 }
350 
351 
352 /* Increase the size of the buffer pointed to by p to at least n symbols.
353  * If insufficient memory, returns NULL and frees the old buffer.
354  */
355 static symbol * increase_size(symbol * p, int n) {
356  symbol * q;
357  int new_size = n + 20;
358  void * mem = realloc((char *) p - HEAD,
359  HEAD + (new_size + 1) * sizeof(symbol));
360  if (mem == NULL) {
361  lose_s(p);
362  return NULL;
363  }
364  q = (symbol *) (HEAD + (char *)mem);
365  CAPACITY(q) = new_size;
366  return q;
367 }
368 
369 /* to replace symbols between c_bra and c_ket in z->p by the
370  s_size symbols at s.
371  Returns 0 on success, -1 on error.
372  Also, frees z->p (and sets it to NULL) on error.
373 */
374 extern int replace_s(struct SN_env * z, int c_bra, int c_ket, int s_size, const symbol * s, int * adjptr)
375 {
376  int adjustment;
377  int len;
378  if (z->p == NULL) {
379  z->p = create_s();
380  if (z->p == NULL) return -1;
381  }
382  adjustment = s_size - (c_ket - c_bra);
383  len = SIZE(z->p);
384  if (adjustment != 0) {
385  if (adjustment + len > CAPACITY(z->p)) {
386  z->p = increase_size(z->p, adjustment + len);
387  if (z->p == NULL) return -1;
388  }
389  memmove(z->p + c_ket + adjustment,
390  z->p + c_ket,
391  (len - c_ket) * sizeof(symbol));
392  SET_SIZE(z->p, adjustment + len);
393  z->l += adjustment;
394  if (z->c >= c_ket)
395  z->c += adjustment;
396  else if (z->c > c_bra)
397  z->c = c_bra;
398  }
399  if (s_size) memmove(z->p + c_bra, s, s_size * sizeof(symbol));
400  if (adjptr != NULL)
401  *adjptr = adjustment;
402  return 0;
403 }
404 
405 static int slice_check(struct SN_env * z) {
406 
407  if (z->bra < 0 ||
408  z->bra > z->ket ||
409  z->ket > z->l ||
410  z->p == NULL ||
411  z->l > SIZE(z->p)) /* this line could be removed */
412  {
413 #if 0
414  fprintf(stderr, "faulty slice operation:\n");
415  debug(z, -1, 0);
416 #endif
417  return -1;
418  }
419  return 0;
420 }
421 
422 extern int slice_from_s(struct SN_env * z, int s_size, const symbol * s) {
423  if (slice_check(z)) return -1;
424  return replace_s(z, z->bra, z->ket, s_size, s, NULL);
425 }
426 
427 extern int slice_from_v(struct SN_env * z, const symbol * p) {
428  return slice_from_s(z, SIZE(p), p);
429 }
430 
431 extern int slice_del(struct SN_env * z) {
432  return slice_from_s(z, 0, 0);
433 }
434 
435 extern int insert_s(struct SN_env * z, int bra, int ket, int s_size, const symbol * s) {
436  int adjustment;
437  if (replace_s(z, bra, ket, s_size, s, &adjustment))
438  return -1;
439  if (bra <= z->bra) z->bra += adjustment;
440  if (bra <= z->ket) z->ket += adjustment;
441  return 0;
442 }
443 
444 extern int insert_v(struct SN_env * z, int bra, int ket, const symbol * p) {
445  return insert_s(z, bra, ket, SIZE(p), p);
446 }
447 
448 extern symbol * slice_to(struct SN_env * z, symbol * p) {
449  if (slice_check(z)) {
450  lose_s(p);
451  return NULL;
452  }
453  {
454  int len = z->ket - z->bra;
455  if (CAPACITY(p) < len) {
456  p = increase_size(p, len);
457  if (p == NULL)
458  return NULL;
459  }
460  memmove(p, z->p + z->bra, len * sizeof(symbol));
461  SET_SIZE(p, len);
462  }
463  return p;
464 }
465 
466 extern symbol * assign_to(struct SN_env * z, symbol * p) {
467  int len = z->l;
468  if (CAPACITY(p) < len) {
469  p = increase_size(p, len);
470  if (p == NULL)
471  return NULL;
472  }
473  memmove(p, z->p, len * sizeof(symbol));
474  SET_SIZE(p, len);
475  return p;
476 }
477 
478 extern int len_utf8(const symbol * p) {
479  int size = SIZE(p);
480  int len = 0;
481  while (size--) {
482  symbol b = *p++;
483  if (b >= 0xC0 || b < 0x80) ++len;
484  }
485  return len;
486 }
487 
488 #if 0
489 extern void debug(struct SN_env * z, int number, int line_count) {
490  int i;
491  int limit = SIZE(z->p);
492  /*if (number >= 0) printf("%3d (line %4d): '", number, line_count);*/
493  if (number >= 0) printf("%3d (line %4d): [%d]'", number, line_count,limit);
494  for (i = 0; i <= limit; i++) {
495  if (z->lb == i) printf("{");
496  if (z->bra == i) printf("[");
497  if (z->c == i) printf("|");
498  if (z->ket == i) printf("]");
499  if (z->l == i) printf("}");
500  if (i < limit)
501  { int ch = z->p[i];
502  if (ch == 0) ch = '#';
503  printf("%c", ch);
504  }
505  }
506  printf("'\n");
507 }
508 #endif
int s_size
Definition: header.h:16
int insert_s(struct SN_env *z, int bra, int ket, int s_size, const symbol *s)
Definition: utilities.c:435
int eq_v_b(struct SN_env *z, const symbol *p)
Definition: utilities.c:229
#define HEAD
Definition: header.h:9
void lose_s(symbol *p)
Definition: utilities.c:15
symbol * p
Definition: api.h:15
int substring_i
Definition: header.h:18
static bool debug
Definition: initdb.c:140
int eq_s_b(struct SN_env *z, int s_size, const symbol *s)
Definition: utilities.c:220
int in_grouping(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:167
int ket
Definition: api.h:16
int slice_del(struct SN_env *z)
Definition: utilities.c:431
int bra
Definition: api.h:16
#define CAPACITY(p)
Definition: header.h:13
int find_among_b(struct SN_env *z, const struct among *v, int v_size)
Definition: utilities.c:298
int in_grouping_b(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:179
#define printf(...)
Definition: port.h:222
int c
Definition: api.h:16
int eq_s(struct SN_env *z, int s_size, const symbol *s)
Definition: utilities.c:215
#define fprintf
Definition: port.h:220
int slice_from_s(struct SN_env *z, int s_size, const symbol *s)
Definition: utilities.c:422
symbol * slice_to(struct SN_env *z, symbol *p)
Definition: utilities.c:448
int slice_from_v(struct SN_env *z, const symbol *p)
Definition: utilities.c:427
#define malloc(a)
Definition: header.h:50
int lb
Definition: api.h:16
Datum repeat(PG_FUNCTION_ARGS)
int in_grouping_U(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:117
int out_grouping_b(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:203
int find_among(struct SN_env *z, const struct among *v, int v_size)
Definition: utilities.c:233
int in_grouping_b_U(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:129
char * c
int out_grouping_b_U(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:153
int eq_v(struct SN_env *z, const symbol *p)
Definition: utilities.c:225
#define SIZE(p)
Definition: header.h:11
#define CREATE_SIZE
Definition: utilities.c:3
int replace_s(struct SN_env *z, int c_bra, int c_ket, int s_size, const symbol *s, int *adjptr)
Definition: utilities.c:374
int(* function)(struct SN_env *)
Definition: header.h:20
int out_grouping_U(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:141
Definition: header.h:15
int result
Definition: header.h:19
const symbol * s
Definition: header.h:17
#define free(a)
Definition: header.h:65
int out_grouping(struct SN_env *z, const unsigned char *s, int min, int max, int repeat)
Definition: utilities.c:191
int len_utf8(const symbol *p)
Definition: utilities.c:478
static int get_b_utf8(const symbol *p, int c, int lb, int *slot)
Definition: utilities.c:93
#define realloc(a, b)
Definition: header.h:60
int skip_b_utf8(const symbol *p, int c, int limit, int n)
Definition: utilities.c:52
int skip_utf8(const symbol *p, int c, int limit, int n)
Definition: utilities.c:27
static symbol * increase_size(symbol *p, int n)
Definition: utilities.c:355
int insert_v(struct SN_env *z, int bra, int ket, const symbol *p)
Definition: utilities.c:444
Definition: api.h:14
int i
static int get_utf8(const symbol *p, int c, int l, int *slot)
Definition: utilities.c:71
#define SET_SIZE(p, n)
Definition: header.h:12
int l
Definition: api.h:16
symbol * create_s(void)
Definition: utilities.c:5
static int slice_check(struct SN_env *z)
Definition: utilities.c:405
symbol * assign_to(struct SN_env *z, symbol *p)
Definition: utilities.c:466
unsigned char symbol
Definition: api.h:2