rstr.c

   1 #include <ctype.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <string.h>
   5 #include "vi.h"
   6
   7 struct rstr {
   8         struct rset *rs;        /* only for regex patterns */
   9         char *str;              /* for simple, non-regex patterns  */
  10         int icase;              /* ignore case */
  11         int lbeg, lend;         /* match line beg/end */
  12         int wbeg, wend;         /* match word beg/end */
  13 };
  14
  15 /* return zero if a simple pattern is given */
  16 static int rstr_simple(struct rstr *rs, char *re)
  17 {
  18         char *beg;
  19         char *end;
  20         rs->lbeg = re[0] == '^';
  21         if (rs->lbeg)
  22                 re++;
  23         rs->wbeg = re[0] == '\\' && re[1] == '<';
  24         if (rs->wbeg)
  25                 re += 2;
  26         beg = re;
  27         while (re[0] && !strchr("\\.*+?[]{}()$", (unsigned char) re[0]))
  28                 re++;
  29         end = re;
  30         rs->wend = re[0] == '\\' && re[1] == '>';
  31         if (rs->wend)
  32                 re += 2;
  33         rs->lend = re[0] == '$';
  34         if (rs->lend)
  35                 re++;
  36         if (!re[0]) {
  37                 int len = end - beg;
  38                 rs->str = malloc(len + 1);
  39                 memcpy(rs->str, beg, len);
  40                 rs->str[len] = '\0';
  41                 return 0;
  42         }
  43         return 1;
  44 }
  45
  46 struct rstr *rstr_make(char *re, int flg)
  47 {
  48         struct rstr *rs = malloc(sizeof(*rs));
  49         memset(rs, 0, sizeof(*rs));
  50         rs->icase = flg & RE_ICASE;
  51         if (rstr_simple(rs, re))
  52                 rs->rs = rset_make(1, &re, flg);
  53         if (!rs->rs && !rs->str) {
  54                 free(rs);
  55                 return NULL;
  56         }
  57         return rs;
  58 }
  59
  60 static int isword(char *s)
  61 {
  62         int c = (unsigned char) s[0];
  63         return isalnum(c) || c == '_' || c > 127;
  64 }
  65
  66 static int match_case(char *s, char *r, int icase)
  67 {
  68         for (; *r && *s; s++, r++) {
  69                 if (!icase && *s != *r)
  70                         return 1;
  71                 if (icase && tolower((unsigned char) *s) != tolower((unsigned char) *r))
  72                         return 1;
  73         }
  74         return *r;
  75 }
  76
  77 /* return zero if an occurrence is found */
  78 int rstr_find(struct rstr *rs, char *s, int n, int *grps, int flg)
  79 {
  80         int len;
  81         char *beg, *end;
  82         char *r;
  83         if (rs->rs)
  84                 return rset_find(rs->rs, s, n, grps, flg);
  85         if ((rs->lbeg && (flg & RE_NOTBOL)) || (rs->lend && (flg & RE_NOTEOL)))
  86                 return -1;
  87         len = strlen(rs->str);
  88         beg = s;
  89         end = s + strlen(s) - len - 1;
  90         if (end < beg)
  91                 return -1;
  92         if (rs->lend)
  93                 beg = end;
  94         if (rs->lbeg)
  95                 end = s;
  96         for (r = beg; r <= end; r++) {
  97                 if (rs->wbeg && r > s && (isword(r - 1) || !isword(r)))
  98                         continue;
  99                 if (rs->wend && r[len] && (!isword(r + len - 1) || isword(r + len)))
 100                         continue;
 101                 if (!match_case(r, rs->str, rs->icase)) {
 102                         if (n >= 1) {
 103                                 grps[0] = r - s;
 104                                 grps[1] = r - s + len;
 105                         }
 106                         return 0;
 107                 }
 108         }
 109         return -1;
 110 }
 111
 112 void rstr_free(struct rstr *rs)
 113 {
 114         if (rs->rs)
 115                 rset_free(rs->rs);
 116         free(rs->str);
 117         free(rs);
 118 }