| 1 | /* regsub.c */ |
| 2 | |
| 3 | /* This file contains the regsub() function, which performs substitutions |
| 4 | * after a regexp match has been found. |
| 5 | */ |
| 6 | |
| 7 | #include "config.h" |
| 8 | #include "ctype.h" |
| 9 | #include "vi.h" |
| 10 | #ifdef REGEX |
| 11 | # include <regex.h> |
| 12 | #else |
| 13 | # include "regexp.h" |
| 14 | #endif |
| 15 | |
| 16 | |
| 17 | /* perform substitutions after a regexp match */ |
| 18 | #ifdef REGEX |
| 19 | void regsub(rm, startp, endp, src, dst) |
| 20 | regmatch_t *rm; /* the regexp with pointers into matched text */ |
| 21 | char *startp, *endp; |
| 22 | REG char *src; /* the replacement string */ |
| 23 | REG char *dst; /* where to put the result of the subst */ |
| 24 | #else |
| 25 | void regsub(re, src, dst) |
| 26 | regexp *re; /* the regexp with pointers into matched text */ |
| 27 | REG char *src; /* the replacement string */ |
| 28 | REG char *dst; /* where to put the result of the subst */ |
| 29 | #endif |
| 30 | { |
| 31 | REG char *cpy; /* pointer to start of text to copy */ |
| 32 | REG char *end; /* pointer to end of text to copy */ |
| 33 | REG char c; |
| 34 | char *start; |
| 35 | #ifndef CRUNCH |
| 36 | int mod = 0;/* used to track \U, \L, \u, \l, and \E */ |
| 37 | int len; /* used to calculate length of subst string */ |
| 38 | static char *prev; /* a copy of the text from the previous subst */ |
| 39 | |
| 40 | /* replace \~ (or maybe ~) by previous substitution text */ |
| 41 | |
| 42 | /* step 1: calculate the length of the new substitution text */ |
| 43 | for (len = strlen(src), c = '\0', cpy = src; *cpy; cpy++) |
| 44 | { |
| 45 | # ifdef NO_MAGIC |
| 46 | if (c == '\\' && *cpy == '~') |
| 47 | # else |
| 48 | if (c == (*o_magic ? '\0' : '\\') && *cpy == '~') |
| 49 | # endif |
| 50 | { |
| 51 | if (!prev) |
| 52 | { |
| 53 | regerr("No prev text to substitute for ~"); |
| 54 | |
| 55 | return; |
| 56 | } |
| 57 | len += strlen(prev) - 1; |
| 58 | # ifndef NO_MAGIC |
| 59 | if (!*o_magic) |
| 60 | # endif |
| 61 | len -= 1; /* because we lose the \ too */ |
| 62 | } |
| 63 | |
| 64 | /* watch backslash quoting */ |
| 65 | if (c != '\\' && *cpy == '\\') |
| 66 | c = '\\'; |
| 67 | else |
| 68 | c = '\0'; |
| 69 | } |
| 70 | |
| 71 | /* allocate memory for the ~ed version of src */ |
| 72 | checkmem(); |
| 73 | start = cpy = (char *)malloc((unsigned)(len + 1)); |
| 74 | if (!cpy) |
| 75 | { |
| 76 | regerr("Not enough memory for ~ expansion"); |
| 77 | return; |
| 78 | } |
| 79 | |
| 80 | /* copy src into start, replacing the ~s by the previous text */ |
| 81 | while (*src) |
| 82 | { |
| 83 | # ifndef NO_MAGIC |
| 84 | if (*o_magic && *src == '~') |
| 85 | { |
| 86 | strcpy(cpy, prev); |
| 87 | cpy += strlen(prev); |
| 88 | src++; |
| 89 | } |
| 90 | else if (!*o_magic && *src == '\\' && *(src + 1) == '~') |
| 91 | # else /* NO_MAGIC */ |
| 92 | if (*src == '\\' && *(src + 1) == '~') |
| 93 | # endif /* NO_MAGIC */ |
| 94 | { |
| 95 | strcpy(cpy, prev); |
| 96 | cpy += strlen(prev); |
| 97 | src += 2; |
| 98 | } |
| 99 | else |
| 100 | { |
| 101 | *cpy++ = *src++; |
| 102 | } |
| 103 | } |
| 104 | *cpy = '\0'; |
| 105 | #ifdef DEBUG |
| 106 | if ((int)(cpy - start) != len) |
| 107 | { |
| 108 | msg("Bug in regsub.c! Predicted length = %d, Actual length = %d", len, (int)(cpy - start)); |
| 109 | } |
| 110 | #endif |
| 111 | checkmem(); |
| 112 | |
| 113 | /* remember this as the "previous" for next time */ |
| 114 | if (prev) |
| 115 | _free_(prev); |
| 116 | prev = src = start; |
| 117 | |
| 118 | #endif /* undef CRUNCH */ |
| 119 | |
| 120 | start = src; |
| 121 | while ((c = *src++) != '\0') |
| 122 | { |
| 123 | #ifndef NO_MAGIC |
| 124 | /* recognize any meta characters */ |
| 125 | if (c == '&' && *o_magic) |
| 126 | { |
| 127 | #ifdef REGEX |
| 128 | cpy = startp; |
| 129 | end = endp; |
| 130 | #else |
| 131 | cpy = re->startp[0]; |
| 132 | end = re->endp[0]; |
| 133 | #endif |
| 134 | } |
| 135 | else |
| 136 | #endif /* not NO_MAGIC */ |
| 137 | if (c == '\\') |
| 138 | { |
| 139 | c = *src++; |
| 140 | switch (c) |
| 141 | { |
| 142 | #ifndef NO_MAGIC |
| 143 | case '0': |
| 144 | case '1': |
| 145 | case '2': |
| 146 | case '3': |
| 147 | case '4': |
| 148 | case '5': |
| 149 | case '6': |
| 150 | case '7': |
| 151 | case '8': |
| 152 | case '9': |
| 153 | /* \0 thru \9 mean "copy subexpression" */ |
| 154 | c -= '0'; |
| 155 | #ifdef REGEX |
| 156 | cpy = startp + (rm[c].rm_so - rm[0].rm_so); |
| 157 | end = endp + (rm[c].rm_eo - rm[0].rm_eo); |
| 158 | #else |
| 159 | cpy = re->startp[c]; |
| 160 | end = re->endp[c]; |
| 161 | #endif |
| 162 | break; |
| 163 | # ifndef CRUNCH |
| 164 | case 'U': |
| 165 | case 'u': |
| 166 | case 'L': |
| 167 | case 'l': |
| 168 | /* \U and \L mean "convert to upper/lowercase" */ |
| 169 | mod = c; |
| 170 | continue; |
| 171 | |
| 172 | case 'E': |
| 173 | case 'e': |
| 174 | /* \E ends the \U or \L */ |
| 175 | mod = 0; |
| 176 | continue; |
| 177 | # endif /* not CRUNCH */ |
| 178 | case '&': |
| 179 | /* "\&" means "original text" */ |
| 180 | if (*o_magic) |
| 181 | { |
| 182 | *dst++ = c; |
| 183 | continue; |
| 184 | } |
| 185 | #ifdef REGEX |
| 186 | cpy = startp; |
| 187 | end = endp; |
| 188 | #else |
| 189 | cpy = re->startp[0]; |
| 190 | end = re->endp[0]; |
| 191 | #endif |
| 192 | break; |
| 193 | |
| 194 | #else /* NO_MAGIC */ |
| 195 | case '&': |
| 196 | /* "\&" means "original text" */ |
| 197 | #ifdef REGEX |
| 198 | cpy = startp; |
| 199 | end = endp; |
| 200 | #else |
| 201 | cpy = re->startp[0]; |
| 202 | end = re->endp[0]; |
| 203 | #endif |
| 204 | break; |
| 205 | #endif /* NO_MAGIC */ |
| 206 | default: |
| 207 | /* ordinary char preceded by backslash */ |
| 208 | *dst++ = c; |
| 209 | continue; |
| 210 | } |
| 211 | } |
| 212 | #ifndef CRUNCH |
| 213 | # if OSK |
| 214 | else if (c == '\l') |
| 215 | # else |
| 216 | else if (c == '\r') |
| 217 | # endif |
| 218 | { |
| 219 | /* transliterate ^M into newline */ |
| 220 | *dst++ = '\n'; |
| 221 | continue; |
| 222 | } |
| 223 | #endif /* !CRUNCH */ |
| 224 | else |
| 225 | { |
| 226 | /* ordinary character, so just copy it */ |
| 227 | *dst++ = c; |
| 228 | continue; |
| 229 | } |
| 230 | |
| 231 | /* Note: to reach this point in the code, we must have evaded |
| 232 | * all "continue" statements. To do that, we must have hit |
| 233 | * a metacharacter that involves copying. |
| 234 | */ |
| 235 | |
| 236 | /* if there is nothing to copy, loop */ |
| 237 | if (!cpy) |
| 238 | continue; |
| 239 | |
| 240 | /* copy over a portion of the original */ |
| 241 | while (cpy < end) |
| 242 | { |
| 243 | #ifndef NO_MAGIC |
| 244 | # ifndef CRUNCH |
| 245 | switch (mod) |
| 246 | { |
| 247 | case 'U': |
| 248 | case 'u': |
| 249 | /* convert to uppercase */ |
| 250 | *dst++ = toupper(*cpy++); |
| 251 | break; |
| 252 | |
| 253 | case 'L': |
| 254 | case 'l': |
| 255 | /* convert to lowercase */ |
| 256 | *dst++ = tolower(*cpy++); |
| 257 | break; |
| 258 | |
| 259 | default: |
| 260 | /* copy without any conversion */ |
| 261 | *dst++ = *cpy++; |
| 262 | } |
| 263 | |
| 264 | /* \u and \l end automatically after the first char */ |
| 265 | if (mod && (mod == 'u' || mod == 'l')) |
| 266 | { |
| 267 | mod = 0; |
| 268 | } |
| 269 | # else /* CRUNCH */ |
| 270 | *dst++ = *cpy++; |
| 271 | # endif /* CRUNCH */ |
| 272 | #else /* NO_MAGIC */ |
| 273 | *dst++ = *cpy++; |
| 274 | #endif /* NO_MAGIC */ |
| 275 | } |
| 276 | } |
| 277 | *dst = '\0'; |
| 278 | } |