buf.c revision 21673
1/* buf.c: This file contains the scratch-file buffer rountines 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 * $FreeBSD: head/bin/ed/buf.c 21673 1997-01-14 07:20:47Z jkh $ 29 */ 30#ifndef lint 31static char * const rcsid = "@(#)buf.c,v 1.4 1994/02/01 00:34:35 alm Exp"; 32#endif /* not lint */ 33 34#include <sys/file.h> 35#include <sys/stat.h> 36 37#include "ed.h" 38 39 40FILE *sfp; /* scratch file pointer */ 41off_t sfseek; /* scratch file position */ 42int seek_write; /* seek before writing */ 43line_t buffer_head; /* incore buffer */ 44 45/* get_sbuf_line: get a line of text from the scratch file; return pointer 46 to the text */ 47char * 48get_sbuf_line(lp) 49 line_t *lp; 50{ 51 static char *sfbuf = NULL; /* buffer */ 52 static int sfbufsz = 0; /* buffer size */ 53 54 int len, ct; 55 56 if (lp == &buffer_head) 57 return NULL; 58 seek_write = 1; /* force seek on write */ 59 /* out of position */ 60 if (sfseek != lp->seek) { 61 sfseek = lp->seek; 62 if (fseek(sfp, sfseek, SEEK_SET) < 0) { 63 fprintf(stderr, "%s\n", strerror(errno)); 64 sprintf(errmsg, "cannot seek temp file"); 65 return NULL; 66 } 67 } 68 len = lp->len; 69 REALLOC(sfbuf, sfbufsz, len + 1, NULL); 70 if ((ct = fread(sfbuf, sizeof(char), len, sfp)) < 0 || ct != len) { 71 fprintf(stderr, "%s\n", strerror(errno)); 72 sprintf(errmsg, "cannot read temp file"); 73 return NULL; 74 } 75 sfseek += len; /* update file position */ 76 sfbuf[len] = '\0'; 77 return sfbuf; 78} 79 80 81/* put_sbuf_line: write a line of text to the scratch file and add a line node 82 to the editor buffer; return a pointer to the end of the text */ 83char * 84put_sbuf_line(cs) 85 char *cs; 86{ 87 line_t *lp; 88 int len, ct; 89 char *s; 90 91 if ((lp = (line_t *) malloc(sizeof(line_t))) == NULL) { 92 fprintf(stderr, "%s\n", strerror(errno)); 93 sprintf(errmsg, "out of memory"); 94 return NULL; 95 } 96 /* assert: cs is '\n' terminated */ 97 for (s = cs; *s != '\n'; s++) 98 ; 99 if (s - cs >= LINECHARS) { 100 sprintf(errmsg, "line too long"); 101 return NULL; 102 } 103 len = s - cs; 104 /* out of position */ 105 if (seek_write) { 106 if (fseek(sfp, 0L, SEEK_END) < 0) { 107 fprintf(stderr, "%s\n", strerror(errno)); 108 sprintf(errmsg, "cannot seek temp file"); 109 return NULL; 110 } 111 sfseek = ftell(sfp); 112 seek_write = 0; 113 } 114 /* assert: SPL1() */ 115 if ((ct = fwrite(cs, sizeof(char), len, sfp)) < 0 || ct != len) { 116 sfseek = -1; 117 fprintf(stderr, "%s\n", strerror(errno)); 118 sprintf(errmsg, "cannot write temp file"); 119 return NULL; 120 } 121 lp->len = len; 122 lp->seek = sfseek; 123 add_line_node(lp); 124 sfseek += len; /* update file position */ 125 return ++s; 126} 127 128 129/* add_line_node: add a line node in the editor buffer after the current line */ 130void 131add_line_node(lp) 132 line_t *lp; 133{ 134 line_t *cp; 135 136 cp = get_addressed_line_node(current_addr); /* this get_addressed_line_node last! */ 137 INSQUE(lp, cp); 138 addr_last++; 139 current_addr++; 140} 141 142 143/* get_line_node_addr: return line number of pointer */ 144long 145get_line_node_addr(lp) 146 line_t *lp; 147{ 148 line_t *cp = &buffer_head; 149 long n = 0; 150 151 while (cp != lp && (cp = cp->q_forw) != &buffer_head) 152 n++; 153 if (n && cp == &buffer_head) { 154 sprintf(errmsg, "invalid address"); 155 return ERR; 156 } 157 return n; 158} 159 160 161/* get_addressed_line_node: return pointer to a line node in the editor buffer */ 162line_t * 163get_addressed_line_node(n) 164 long n; 165{ 166 static line_t *lp = &buffer_head; 167 static long on = 0; 168 169 SPL1(); 170 if (n > on) 171 if (n <= (on + addr_last) >> 1) 172 for (; on < n; on++) 173 lp = lp->q_forw; 174 else { 175 lp = buffer_head.q_back; 176 for (on = addr_last; on > n; on--) 177 lp = lp->q_back; 178 } 179 else 180 if (n >= on >> 1) 181 for (; on > n; on--) 182 lp = lp->q_back; 183 else { 184 lp = &buffer_head; 185 for (on = 0; on < n; on++) 186 lp = lp->q_forw; 187 } 188 SPL0(); 189 return lp; 190} 191 192 193extern int newline_added; 194 195char sfn[15] = ""; /* scratch file name */ 196 197/* open_sbuf: open scratch file */ 198int 199open_sbuf() 200{ 201 int u; 202 203 isbinary = newline_added = 0; 204 u = umask(077); 205 strcpy(sfn, "/tmp/ed.XXXXXX"); 206 if (mktemp(sfn) == NULL || (sfp = fopen(sfn, "w+")) == NULL) { 207 fprintf(stderr, "%s: %s\n", sfn, strerror(errno)); 208 sprintf(errmsg, "cannot open temp file"); 209 umask(u); 210 return ERR; 211 } 212 umask(u); 213 return 0; 214} 215 216 217/* close_sbuf: close scratch file */ 218int 219close_sbuf() 220{ 221 if (sfp) { 222 if (fclose(sfp) < 0) { 223 fprintf(stderr, "%s: %s\n", sfn, strerror(errno)); 224 sprintf(errmsg, "cannot close temp file"); 225 return ERR; 226 } 227 sfp = NULL; 228 unlink(sfn); 229 } 230 sfseek = seek_write = 0; 231 return 0; 232} 233 234 235/* quit: remove_lines scratch file and exit */ 236void 237quit(n) 238 int n; 239{ 240 if (sfp) { 241 fclose(sfp); 242 unlink(sfn); 243 } 244 exit(n); 245} 246 247 248unsigned char ctab[256]; /* character translation table */ 249 250/* init_buffers: open scratch buffer; initialize line queue */ 251void 252init_buffers() 253{ 254 int i = 0; 255 256 /* Read stdin one character at a time to avoid i/o contention 257 with shell escapes invoked by nonterminal input, e.g., 258 ed - <<EOF 259 !cat 260 hello, world 261 EOF */ 262 setbuffer(stdin, stdinbuf, 1); 263 if (open_sbuf() < 0) 264 quit(2); 265 REQUE(&buffer_head, &buffer_head); 266 for (i = 0; i < 256; i++) 267 ctab[i] = i; 268} 269 270 271/* translit_text: translate characters in a string */ 272char * 273translit_text(s, len, from, to) 274 char *s; 275 int len; 276 int from; 277 int to; 278{ 279 static int i = 0; 280 281 unsigned char *us; 282 283 ctab[i] = i; /* restore table to initial state */ 284 ctab[i = from] = to; 285 for (us = (unsigned char *) s; len-- > 0; us++) 286 *us = ctab[*us]; 287 return s; 288} 289