1 /* buf.c: This file contains the scratch-file buffer routines for the 2 ed line editor. */ 3 /*- 4 * Copyright (c) 1993 Andrew Moore, Talke Studio. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * @(#)buf.c,v 1.4 1994/02/01 00:34:35 alm Exp 29 * $FreeBSD: src/bin/ed/buf.c,v 1.22 2002/06/30 05:13:53 obrien Exp $ 30 * $DragonFly: src/bin/ed/buf.c,v 1.4 2007/04/06 23:36:54 pavalos Exp $ 31 */ 32 33 #include <sys/file.h> 34 #include <sys/stat.h> 35 36 #include "ed.h" 37 38 39 FILE *sfp; /* scratch file pointer */ 40 off_t sfseek; /* scratch file position */ 41 int seek_write; /* seek before writing */ 42 line_t buffer_head; /* incore buffer */ 43 44 /* get_sbuf_line: get a line of text from the scratch file; return pointer 45 to the text */ 46 char * 47 get_sbuf_line(line_t *lp) 48 { 49 static char *sfbuf = NULL; /* buffer */ 50 static int sfbufsz = 0; /* buffer size */ 51 52 int len, ct; 53 54 if (lp == &buffer_head) 55 return NULL; 56 seek_write = 1; /* force seek on write */ 57 /* out of position */ 58 if (sfseek != lp->seek) { 59 sfseek = lp->seek; 60 if (fseeko(sfp, sfseek, SEEK_SET) < 0) { 61 fprintf(stderr, "%s\n", strerror(errno)); 62 errmsg = "cannot seek temp file"; 63 return NULL; 64 } 65 } 66 len = lp->len; 67 REALLOC(sfbuf, sfbufsz, len + 1, NULL); 68 if ((ct = fread(sfbuf, sizeof(char), len, sfp)) < 0 || ct != len) { 69 fprintf(stderr, "%s\n", strerror(errno)); 70 errmsg = "cannot read temp file"; 71 return NULL; 72 } 73 sfseek += len; /* update file position */ 74 sfbuf[len] = '\0'; 75 return sfbuf; 76 } 77 78 79 /* put_sbuf_line: write a line of text to the scratch file and add a line node 80 to the editor buffer; return a pointer to the end of the text */ 81 const char * 82 put_sbuf_line(const char *cs) 83 { 84 line_t *lp; 85 int len, ct; 86 const char *s; 87 88 if ((lp = (line_t *) malloc(sizeof(line_t))) == NULL) { 89 fprintf(stderr, "%s\n", strerror(errno)); 90 errmsg = "out of memory"; 91 return NULL; 92 } 93 /* assert: cs is '\n' terminated */ 94 for (s = cs; *s != '\n'; s++) 95 ; 96 if (s - cs >= LINECHARS) { 97 errmsg = "line too long"; 98 return NULL; 99 } 100 len = s - cs; 101 /* out of position */ 102 if (seek_write) { 103 if (fseeko(sfp, (off_t)0, SEEK_END) < 0) { 104 fprintf(stderr, "%s\n", strerror(errno)); 105 errmsg = "cannot seek temp file"; 106 return NULL; 107 } 108 sfseek = ftello(sfp); 109 seek_write = 0; 110 } 111 /* assert: SPL1() */ 112 if ((ct = fwrite(cs, sizeof(char), len, sfp)) < 0 || ct != len) { 113 sfseek = -1; 114 fprintf(stderr, "%s\n", strerror(errno)); 115 errmsg = "cannot write temp file"; 116 return NULL; 117 } 118 lp->len = len; 119 lp->seek = sfseek; 120 add_line_node(lp); 121 sfseek += len; /* update file position */ 122 return ++s; 123 } 124 125 126 /* add_line_node: add a line node in the editor buffer after the current line */ 127 void 128 add_line_node(line_t *lp) 129 { 130 line_t *cp; 131 132 cp = get_addressed_line_node(current_addr); /* this get_addressed_line_node last! */ 133 INSQUE(lp, cp); 134 addr_last++; 135 current_addr++; 136 } 137 138 139 /* get_line_node_addr: return line number of pointer */ 140 long 141 get_line_node_addr(line_t *lp) 142 { 143 line_t *cp = &buffer_head; 144 long n = 0; 145 146 while (cp != lp && (cp = cp->q_forw) != &buffer_head) 147 n++; 148 if (n && cp == &buffer_head) { 149 errmsg = "invalid address"; 150 return ERR; 151 } 152 return n; 153 } 154 155 156 /* get_addressed_line_node: return pointer to a line node in the editor buffer */ 157 line_t * 158 get_addressed_line_node(long n) 159 { 160 static line_t *lp = &buffer_head; 161 static long on = 0; 162 163 SPL1(); 164 if (n > on) 165 if (n <= (on + addr_last) >> 1) 166 for (; on < n; on++) 167 lp = lp->q_forw; 168 else { 169 lp = buffer_head.q_back; 170 for (on = addr_last; on > n; on--) 171 lp = lp->q_back; 172 } 173 else 174 if (n >= on >> 1) 175 for (; on > n; on--) 176 lp = lp->q_back; 177 else { 178 lp = &buffer_head; 179 for (on = 0; on < n; on++) 180 lp = lp->q_forw; 181 } 182 SPL0(); 183 return lp; 184 } 185 186 187 extern int newline_added; 188 189 char sfn[15] = ""; /* scratch file name */ 190 191 /* open_sbuf: open scratch file */ 192 int 193 open_sbuf(void) 194 { 195 int fd; 196 int u; 197 198 isbinary = newline_added = 0; 199 u = umask(077); 200 strcpy(sfn, "/tmp/ed.XXXXXX"); 201 if ((fd = mkstemp(sfn)) == -1 || 202 (sfp = fdopen(fd, "w+")) == NULL) { 203 if (fd != -1) 204 close(fd); 205 perror(sfn); 206 errmsg = "cannot open temp file"; 207 umask(u); 208 return ERR; 209 } 210 umask(u); 211 return 0; 212 } 213 214 215 /* close_sbuf: close scratch file */ 216 int 217 close_sbuf(void) 218 { 219 if (sfp) { 220 if (fclose(sfp) < 0) { 221 fprintf(stderr, "%s: %s\n", sfn, strerror(errno)); 222 errmsg = "cannot close temp file"; 223 return ERR; 224 } 225 sfp = NULL; 226 unlink(sfn); 227 } 228 sfseek = seek_write = 0; 229 return 0; 230 } 231 232 233 /* quit: remove_lines scratch file and exit */ 234 void 235 quit(int n) 236 { 237 if (sfp) { 238 fclose(sfp); 239 unlink(sfn); 240 } 241 exit(n); 242 } 243 244 245 unsigned char ctab[256]; /* character translation table */ 246 247 /* init_buffers: open scratch buffer; initialize line queue */ 248 void 249 init_buffers(void) 250 { 251 int i = 0; 252 253 /* Read stdin one character at a time to avoid i/o contention 254 with shell escapes invoked by nonterminal input, e.g., 255 ed - <<EOF 256 !cat 257 hello, world 258 EOF */ 259 setbuffer(stdin, stdinbuf, 1); 260 261 /* Ensure stdout is line buffered. This avoids bogus delays 262 of output if stdout is piped through utilities to a terminal. */ 263 setvbuf(stdout, NULL, _IOLBF, 0); 264 if (open_sbuf() < 0) 265 quit(2); 266 REQUE(&buffer_head, &buffer_head); 267 for (i = 0; i < 256; i++) 268 ctab[i] = i; 269 } 270 271 272 /* translit_text: translate characters in a string */ 273 char * 274 translit_text(char *s, int len, int from, int to) 275 { 276 static int i = 0; 277 278 unsigned char *us; 279 280 ctab[i] = i; /* restore table to initial state */ 281 ctab[i = from] = to; 282 for (us = (unsigned char *) s; len-- > 0; us++) 283 *us = ctab[*us]; 284 return s; 285 } 286