1 /* $OpenBSD: ed.c,v 1.2 2016/02/22 19:31:38 tobias Exp $ */ 2 3 /* 4 * Copyright (c) 2015 Tobias Stoeckmann <tobias@openbsd.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #include <sys/queue.h> 20 #include <sys/stat.h> 21 22 #include <ctype.h> 23 #include <stdio.h> 24 #include <stdlib.h> 25 #include <string.h> 26 27 #include "common.h" 28 #include "util.h" 29 #include "pch.h" 30 #include "inp.h" 31 32 /* states of finite state machine */ 33 #define FSM_CMD 1 34 #define FSM_A 2 35 #define FSM_C 3 36 #define FSM_D 4 37 #define FSM_I 5 38 #define FSM_S 6 39 40 #define SRC_INP 1 /* line's origin is input file */ 41 #define SRC_PCH 2 /* line's origin is patch file */ 42 43 #define S_PATTERN "/.//" 44 45 static void init_lines(void); 46 static void free_lines(void); 47 static struct ed_line *get_line(LINENUM); 48 static struct ed_line *create_line(off_t); 49 static int valid_addr(LINENUM, LINENUM); 50 static int get_command(void); 51 static void write_lines(char *); 52 53 LIST_HEAD(ed_head, ed_line) head; 54 struct ed_line { 55 LIST_ENTRY(ed_line) entries; 56 int src; 57 unsigned long subst; 58 union { 59 LINENUM lineno; 60 off_t seek; 61 } pos; 62 }; 63 64 static LINENUM first_addr; 65 static LINENUM second_addr; 66 static LINENUM line_count; 67 static struct ed_line *cline; /* current line */ 68 69 void 70 do_ed_script(void) 71 { 72 off_t linepos; 73 struct ed_line *nline; 74 LINENUM i, range; 75 int fsm; 76 77 init_lines(); 78 cline = NULL; 79 fsm = FSM_CMD; 80 81 for (;;) { 82 linepos = ftello(pfp); 83 if (pgets(buf, sizeof buf, pfp) == NULL) 84 break; 85 p_input_line++; 86 87 if (fsm == FSM_CMD) { 88 if ((fsm = get_command()) == -1) 89 break; 90 91 switch (fsm) { 92 case FSM_C: 93 case FSM_D: 94 /* delete lines in specified range */ 95 if (second_addr == -1) 96 range = 1; 97 else 98 range = second_addr - first_addr + 1; 99 for (i = 0; i < range; i++) { 100 nline = LIST_NEXT(cline, entries); 101 LIST_REMOVE(cline, entries); 102 free(cline); 103 cline = nline; 104 line_count--; 105 } 106 fsm = (fsm == FSM_C) ? FSM_I : FSM_CMD; 107 break; 108 case FSM_S: 109 cline->subst++; 110 fsm = FSM_CMD; 111 break; 112 default: 113 break; 114 } 115 116 continue; 117 } 118 119 if (strcmp(buf, ".\n") == 0) { 120 fsm = FSM_CMD; 121 continue; 122 } 123 124 nline = create_line(linepos); 125 if (cline == NULL) 126 LIST_INSERT_HEAD(&head, nline, entries); 127 else if (fsm == FSM_A) 128 LIST_INSERT_AFTER(cline, nline, entries); 129 else 130 LIST_INSERT_BEFORE(cline, nline, entries); 131 cline = nline; 132 line_count++; 133 fsm = FSM_A; 134 } 135 136 next_intuit_at(linepos, p_input_line); 137 138 if (skip_rest_of_patch) { 139 free_lines(); 140 return; 141 } 142 143 write_lines(TMPOUTNAME); 144 free_lines(); 145 146 ignore_signals(); 147 if (!check_only) { 148 if (move_file(TMPOUTNAME, outname) < 0) { 149 toutkeep = true; 150 chmod(TMPOUTNAME, filemode); 151 } else 152 chmod(outname, filemode); 153 } 154 set_signals(1); 155 } 156 157 static int 158 get_command(void) 159 { 160 char *p; 161 LINENUM min_addr; 162 int fsm; 163 164 min_addr = 0; 165 fsm = -1; 166 p = buf; 167 168 /* maybe garbage encountered at end of patch */ 169 if (!isdigit((unsigned char)*p)) 170 return -1; 171 172 first_addr = strtolinenum(buf, &p); 173 second_addr = (*p == ',') ? strtolinenum(p + 1, &p) : -1; 174 175 switch (*p++) { 176 case 'a': 177 if (second_addr != -1) 178 fatal("invalid address at line %ld: %s", 179 p_input_line, buf); 180 fsm = FSM_A; 181 break; 182 case 'c': 183 fsm = FSM_C; 184 min_addr = 1; 185 break; 186 case 'd': 187 fsm = FSM_D; 188 min_addr = 1; 189 break; 190 case 'i': 191 if (second_addr != -1) 192 fatal("invalid address at line %ld: %s", 193 p_input_line, buf); 194 fsm = FSM_I; 195 break; 196 case 's': 197 if (second_addr != -1) 198 fatal("unsupported address range at line %ld: %s", 199 p_input_line, buf); 200 if (strncmp(p, S_PATTERN, sizeof(S_PATTERN) - 1) != 0) 201 fatal("unsupported substitution at " 202 "line %ld: %s", p_input_line, buf); 203 p += sizeof(S_PATTERN) - 1; 204 fsm = FSM_S; 205 min_addr = 1; 206 break; 207 default: 208 return -1; 209 /* NOTREACHED */ 210 } 211 212 if (*p != '\n') 213 return -1; 214 215 if (!valid_addr(first_addr, min_addr) || 216 (second_addr != -1 && !valid_addr(second_addr, first_addr))) 217 fatal("invalid address at line %ld: %s", p_input_line, buf); 218 219 cline = get_line(first_addr); 220 221 return fsm; 222 } 223 224 static void 225 write_lines(char *filename) 226 { 227 FILE *ofp; 228 char *p; 229 struct ed_line *line; 230 off_t linepos; 231 232 linepos = ftello(pfp); 233 ofp = fopen(filename, "w"); 234 if (ofp == NULL) 235 pfatal("can't create %s", filename); 236 237 LIST_FOREACH(line, &head, entries) { 238 if (line->src == SRC_INP) { 239 p = ifetch(line->pos.lineno, 0); 240 /* Note: string is not NUL terminated. */ 241 for (; *p != '\n'; p++) 242 if (line->subst != 0) 243 line->subst--; 244 else 245 putc(*p, ofp); 246 putc('\n', ofp); 247 } else if (line->src == SRC_PCH) { 248 fseeko(pfp, line->pos.seek, SEEK_SET); 249 if (pgets(buf, sizeof buf, pfp) == NULL) 250 fatal("unexpected end of file"); 251 p = buf; 252 if (line->subst != 0) 253 for (; *p != '\0' && *p != '\n'; p++) 254 if (line->subst-- == 0) 255 break; 256 fputs(p, ofp); 257 if (strchr(p, '\n') == NULL) 258 putc('\n', ofp); 259 } 260 } 261 fclose(ofp); 262 263 /* restore patch file position to match p_input_line */ 264 fseeko(pfp, linepos, SEEK_SET); 265 } 266 267 /* initialize list with input file */ 268 static void 269 init_lines(void) 270 { 271 struct ed_line *line; 272 LINENUM i; 273 274 LIST_INIT(&head); 275 for (i = input_lines; i > 0; i--) { 276 line = malloc(sizeof(*line)); 277 if (line == NULL) 278 fatal("cannot allocate memory"); 279 line->src = SRC_INP; 280 line->subst = 0; 281 line->pos.lineno = i; 282 LIST_INSERT_HEAD(&head, line, entries); 283 } 284 line_count = input_lines; 285 } 286 287 static void 288 free_lines(void) 289 { 290 struct ed_line *line; 291 292 while (!LIST_EMPTY(&head)) { 293 line = LIST_FIRST(&head); 294 LIST_REMOVE(line, entries); 295 free(line); 296 } 297 } 298 299 static struct ed_line * 300 get_line(LINENUM lineno) 301 { 302 struct ed_line *line; 303 LINENUM i; 304 305 if (lineno == 0) 306 return NULL; 307 308 i = 0; 309 LIST_FOREACH(line, &head, entries) 310 if (++i == lineno) 311 return line; 312 313 return NULL; 314 } 315 316 static struct ed_line * 317 create_line(off_t seek) 318 { 319 struct ed_line *line; 320 321 line = malloc(sizeof(*line)); 322 if (line == NULL) 323 fatal("cannot allocate memory"); 324 line->src = SRC_PCH; 325 line->subst = 0; 326 line->pos.seek = seek; 327 328 return line; 329 } 330 331 static int 332 valid_addr(LINENUM lineno, LINENUM min) 333 { 334 return lineno >= min && lineno <= line_count; 335 } 336