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
|
/* regex.c: regular expression interface routines for the ed line editor. */
/* GNU ed - The GNU line editor.
Copyright (C) 1993, 1994 Andrew Moore, Talke Studio
Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014
Free Software Foundation, Inc.
This program 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 3 of the License, or
(at your option) any later version.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <stddef.h>
#include <errno.h>
#include <sys/types.h>
#include <regex.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "ed.h"
static regex_t * global_pat = 0;
static bool patlock = false; /* if set, pattern not freed by get_compiled_pattern */
static char * stbuf = 0; /* substitution template buffer */
static int stbufsz = 0; /* substitution template buffer size */
static int stlen = 0; /* substitution template length */
static char * rbuf = 0; /* replace_matching_text buffer */
static int rbufsz = 0; /* replace_matching_text buffer size */
bool prev_pattern( void ) { return global_pat != 0; }
/* translate characters in a string */
static void translit_text( char * p, int len, const char from, const char to )
{
while( --len >= 0 )
{
if( *p == from ) *p = to;
++p;
}
}
/* overwrite newlines with ASCII NULs */
static void newline_to_nul( char * const s, const int len )
{ translit_text( s, len, '\n', '\0' ); }
/* overwrite ASCII NULs with newlines */
static void nul_to_newline( char * const s, const int len )
{ translit_text( s, len, '\0', '\n' ); }
/* expand a POSIX character class */
static const char * parse_char_class( const char * p )
{
char c, d;
if( *p == '^' ) ++p;
if( *p == ']' ) ++p;
for( ; *p != ']' && *p != '\n'; ++p )
if( *p == '[' && ( ( d = p[1] ) == '.' || d == ':' || d == '=' ) )
for( ++p, c = *++p; *p != ']' || c != d; ++p )
if( ( c = *p ) == '\n' )
return 0;
return ( ( *p == ']' ) ? p : 0 );
}
/* copy a pattern string from the command buffer; return pointer to the copy */
static char * extract_pattern( const char ** const ibufpp, const char delimiter )
{
static char * buf = 0;
static int bufsz = 0;
const char * nd = *ibufpp;
int len;
while( *nd != delimiter && *nd != '\n' )
{
if( *nd == '[' )
{
nd = parse_char_class( ++nd );
if( !nd ) { set_error_msg( "Unbalanced brackets ([])" ); return 0; }
}
else if( *nd == '\\' && *++nd == '\n' )
{ set_error_msg( "Trailing backslash (\\)" ); return 0; }
++nd;
}
len = nd - *ibufpp;
if( !resize_buffer( &buf, &bufsz, len + 1 ) ) return 0;
memcpy( buf, *ibufpp, len );
buf[len] = 0;
*ibufpp = nd;
if( isbinary() ) nul_to_newline( buf, len );
return buf;
}
/* return pointer to compiled pattern from command buffer */
static regex_t * get_compiled_pattern( const char ** const ibufpp )
{
static regex_t * exp = 0;
const char * exps;
const char delimiter = **ibufpp;
int n;
if( delimiter == ' ' )
{ set_error_msg( "Invalid pattern delimiter" ); return 0; }
if( delimiter == '\n' || *++*ibufpp == '\n' || **ibufpp == delimiter )
{
if( !exp ) set_error_msg( "No previous pattern" );
return exp;
}
exps = extract_pattern( ibufpp, delimiter );
if( !exps ) return 0;
/* buffer alloc'd && not reserved */
if( exp && !patlock ) regfree( exp );
else
{
exp = (regex_t *) malloc( sizeof (regex_t) );
if( !exp )
{
show_strerror( 0, errno );
set_error_msg( "Memory exhausted" );
return 0;
}
}
patlock = false;
n = regcomp( exp, exps, 0 );
if( n )
{
char buf[80];
regerror( n, exp, buf, sizeof buf );
set_error_msg( buf );
free( exp );
exp = 0;
}
return exp;
}
/* add line matching a pattern to the global-active list */
bool build_active_list( const char ** const ibufpp, const int first_addr,
const int second_addr, const bool match )
{
const regex_t * pat;
const line_t * lp;
int addr;
const char delimiter = **ibufpp;
if( delimiter == ' ' || delimiter == '\n' )
{ set_error_msg( "Invalid pattern delimiter" ); return false; }
pat = get_compiled_pattern( ibufpp );
if( !pat ) return false;
if( **ibufpp == delimiter ) ++*ibufpp;
clear_active_list();
lp = search_line_node( first_addr );
for( addr = first_addr; addr <= second_addr; ++addr, lp = lp->q_forw )
{
char * const s = get_sbuf_line( lp );
if( !s ) return false;
if( isbinary() ) nul_to_newline( s, lp->len );
if( !regexec( pat, s, 0, 0, 0 ) == match && !set_active_node( lp ) )
return false;
}
return true;
}
/* return pointer to copy of substitution template in the command buffer */
static char * extract_subst_template( const char ** const ibufpp,
const bool isglobal )
{
int i = 0, n = 0;
char c;
const char delimiter = **ibufpp;
++*ibufpp;
if( **ibufpp == '%' && (*ibufpp)[1] == delimiter )
{
++*ibufpp;
if( !stbuf ) set_error_msg( "No previous substitution" );
return stbuf;
}
while( **ibufpp != delimiter )
{
if( !resize_buffer( &stbuf, &stbufsz, i + 2 ) ) return 0;
c = stbuf[i++] = *(*ibufpp)++;
if( c == '\n' && **ibufpp == 0 ) { --i, --*ibufpp; break; }
if( c == '\\' && ( stbuf[i++] = *(*ibufpp)++ ) == '\n' && !isglobal )
{
while( ( *ibufpp = get_tty_line( &n ) ) &&
( n == 0 || ( n > 0 && (*ibufpp)[n-1] != '\n' ) ) )
clearerr( stdin );
if( !*ibufpp ) return 0;
}
}
if( !resize_buffer( &stbuf, &stbufsz, i + 1 ) ) return 0;
stbuf[stlen = i] = 0;
return stbuf;
}
/* extract substitution tail from the command buffer */
bool extract_subst_tail( const char ** const ibufpp, int * const gflagsp,
int * const snump, const bool isglobal )
{
const char delimiter = **ibufpp;
*gflagsp = *snump = 0;
if( delimiter == '\n' ) { stlen = 0; *gflagsp = GPR; return true; }
if( !extract_subst_template( ibufpp, isglobal ) ) return false;
if( **ibufpp == '\n' ) { *gflagsp = GPR; return true; }
if( **ibufpp == delimiter ) ++*ibufpp;
if( **ibufpp >= '1' && **ibufpp <= '9' )
return parse_int( snump, *ibufpp, ibufpp );
if( **ibufpp == 'g' ) { ++*ibufpp; *gflagsp = GSG; }
return true;
}
/* return the address of the next line matching a pattern in a given
direction. wrap around begin/end of editor buffer if necessary */
int next_matching_node_addr( const char ** const ibufpp, const bool forward )
{
const regex_t * const pat = get_compiled_pattern( ibufpp );
int addr = current_addr();
if( !pat ) return -1;
do {
addr = ( forward ? inc_addr( addr ) : dec_addr( addr ) );
if( addr )
{
const line_t * const lp = search_line_node( addr );
char * const s = get_sbuf_line( lp );
if( !s ) return -1;
if( isbinary() ) nul_to_newline( s, lp->len );
if( !regexec( pat, s, 0, 0, 0 ) ) return addr;
}
}
while( addr != current_addr() );
set_error_msg( "No match" );
return -1;
}
bool new_compiled_pattern( const char ** const ibufpp )
{
regex_t * tpat;
disable_interrupts();
tpat = get_compiled_pattern( ibufpp );
if( tpat && tpat != global_pat )
{
if( global_pat ) { regfree( global_pat ); free( global_pat ); }
global_pat = tpat;
patlock = true; /* reserve pattern */
}
enable_interrupts();
return ( tpat ? true : false );
}
/* modify text according to a substitution template; return offset to
end of modified text */
static int apply_subst_template( const char * const boln,
const regmatch_t * const rm, int offset,
const int re_nsub )
{
const char * sub = stbuf;
for( ; sub - stbuf < stlen; ++sub )
{
int n;
if( *sub == '&' )
{
int j = rm[0].rm_so; int k = rm[0].rm_eo;
if( !resize_buffer( &rbuf, &rbufsz, offset + k - j ) ) return -1;
while( j < k ) rbuf[offset++] = boln[j++];
}
else if( *sub == '\\' && *++sub >= '1' && *sub <= '9' &&
( n = *sub - '0' ) <= re_nsub )
{
int j = rm[n].rm_so; int k = rm[n].rm_eo;
if( !resize_buffer( &rbuf, &rbufsz, offset + k - j ) ) return -1;
while( j < k ) rbuf[offset++] = boln[j++];
}
else
{
if( !resize_buffer( &rbuf, &rbufsz, offset + 1 ) ) return -1;
rbuf[offset++] = *sub;
}
}
if( !resize_buffer( &rbuf, &rbufsz, offset + 1 ) ) return -1;
rbuf[offset] = 0;
return offset;
}
/* replace text matched by a pattern according to a substitution
template; return size of the modified text */
static int replace_matching_text( const line_t * const lp, const int gflags,
const int snum )
{
enum { se_max = 30 }; /* max subexpressions in a regular expression */
regmatch_t rm[se_max];
char * txt = get_sbuf_line( lp );
const char * eot;
int i = 0, offset = 0;
bool changed = false;
if( !txt ) return -1;
if( isbinary() ) nul_to_newline( txt, lp->len );
eot = txt + lp->len;
if( !regexec( global_pat, txt, se_max, rm, 0 ) )
{
int matchno = 0;
do {
if( !snum || snum == ++matchno )
{
changed = true; i = rm[0].rm_so;
if( !resize_buffer( &rbuf, &rbufsz, offset + i ) ) return -1;
if( isbinary() ) newline_to_nul( txt, rm[0].rm_eo );
memcpy( rbuf + offset, txt, i ); offset += i;
offset = apply_subst_template( txt, rm, offset, global_pat->re_nsub );
if( offset < 0 ) return -1;
}
else
{
i = rm[0].rm_eo;
if( !resize_buffer( &rbuf, &rbufsz, offset + i ) ) return -1;
if( isbinary() ) newline_to_nul( txt, i );
memcpy( rbuf + offset, txt, i ); offset += i;
}
txt += rm[0].rm_eo;
}
while( *txt && ( !changed || ( ( gflags & GSG ) && rm[0].rm_eo ) ) &&
!regexec( global_pat, txt, se_max, rm, REG_NOTBOL ) );
i = eot - txt;
if( !resize_buffer( &rbuf, &rbufsz, offset + i + 2 ) ) return -1;
if( i > 0 && !rm[0].rm_eo && ( gflags & GSG ) )
{ set_error_msg( "Infinite substitution loop" ); return -1; }
if( isbinary() ) newline_to_nul( txt, i );
memcpy( rbuf + offset, txt, i );
memcpy( rbuf + offset + i, "\n", 2 );
}
return ( changed ? offset + i + 1 : 0 );
}
/* for each line in a range, change text matching a pattern according to
a substitution template; return false if error */
bool search_and_replace( const int first_addr, const int second_addr,
const int gflags, const int snum, const bool isglobal )
{
int lc;
bool match_found = false;
set_current_addr( first_addr - 1 );
for( lc = 0; lc <= second_addr - first_addr; ++lc )
{
const line_t * const lp = search_line_node( inc_current_addr() );
const int size = replace_matching_text( lp, gflags, snum );
if( size < 0 ) return false;
if( size )
{
const char * txt = rbuf;
const char * const eot = rbuf + size;
undo_t * up = 0;
disable_interrupts();
if( !delete_lines( current_addr(), current_addr(), isglobal ) )
{ enable_interrupts(); return false; }
do {
txt = put_sbuf_line( txt, size, current_addr() );
if( !txt ) { enable_interrupts(); return false; }
if( up ) up->tail = search_line_node( current_addr() );
else
{
up = push_undo_atom( UADD, current_addr(), current_addr() );
if( !up ) { enable_interrupts(); return false; }
}
}
while( txt != eot );
enable_interrupts();
match_found = true;
}
}
if( !match_found && !( gflags & GLB ) )
{ set_error_msg( "No match" ); return false; }
return true;
}
|