bin/ed/buf.c

   1 /*      $NetBSD: buf.c,v 1.25 2005/06/26 19:10:49 christos Exp $        */
   2
   3 /* buf.c: This file contains the scratch-file buffer routines for the
   4    ed line editor. */
   5 /*-
   6  * Copyright (c) 1993 Andrew Moore, Talke Studio.
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  *
  18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  28  * SUCH DAMAGE.
  29  */
  30
  31 #include <sys/cdefs.h>
  32 #ifndef lint
  33 #if 0
  34 static char *rcsid = "@(#)buf.c,v 1.4 1994/02/01 00:34:35 alm Exp";
  35 #else
  36 __RCSID("$NetBSD: buf.c,v 1.25 2005/06/26 19:10:49 christos Exp $");
  37 #endif
  38 #endif /* not lint */
  39
  40 #include <sys/file.h>
  41 #include <sys/stat.h>
  42
  43 #include <paths.h>
  44 #include <stdio.h>
  45 #include <err.h>
  46
  47 #include "ed.h"
  48
  49
  50 FILE *sfp;                              /* scratch file pointer */
  51 off_t sfseek;                           /* scratch file position */
  52 int seek_write;                         /* seek before writing */
  53 line_t buffer_head;                     /* incore buffer */
  54
  55 /* get_sbuf_line: get a line of text from the scratch file; return pointer
  56    to the text */
  57 char *
  58 get_sbuf_line(line_t *lp)
  59 {
  60         static char *sfbuf = NULL;      /* buffer */
  61         static int sfbufsz = 0;         /* buffer size */
  62
  63         int len, ct;
  64
  65         if (lp == &buffer_head)
  66                 return NULL;
  67         seek_write = 1;                         /* force seek on write */
  68         /* out of position */
  69         if (sfseek != lp->seek) {
  70                 sfseek = lp->seek;
  71                 if (fseek(sfp, sfseek, SEEK_SET) < 0) {
  72                         fprintf(stderr, "%s\n", strerror(errno));
  73                         sprintf(errmsg, "cannot seek temp file");
  74                         return NULL;
  75                 }
  76         }
  77         len = lp->len;
  78         REALLOC(sfbuf, sfbufsz, len + 1, NULL);
  79         if ((ct = fread(sfbuf, sizeof(char), len, sfp)) <  0 || ct != len) {
  80                 fprintf(stderr, "%s\n", strerror(errno));
  81                 sprintf(errmsg, "cannot read temp file");
  82                 return NULL;
  83         }
  84         sfseek += len;                          /* update file position */
  85         sfbuf[len] = '\0';
  86         return sfbuf;
  87 }
  88
  89
  90 /* put_sbuf_line: write a line of text to the scratch file and add a line node
  91    to the editor buffer;  return a pointer to the end of the text */
  92 char *
  93 put_sbuf_line(char *cs)
  94 {
  95         line_t *lp;
  96         int len, ct;
  97         char *s;
  98
  99         if ((lp = (line_t *) malloc(sizeof(line_t))) == NULL) {
 100                 fprintf(stderr, "%s\n", strerror(errno));
 101                 sprintf(errmsg, "out of memory");
 102                 return NULL;
 103         }
 104         /* assert: cs is '\n' terminated */
 105         for (s = cs; *s != '\n'; s++)
 106                 ;
 107         if (s - cs >= LINECHARS) {
 108                 sprintf(errmsg, "line too long");
 109                 free(lp);
 110                 return NULL;
 111         }
 112         len = s - cs;
 113         /* out of position */
 114         if (seek_write) {
 115                 if (fseek(sfp, 0L, SEEK_END) < 0) {
 116                         fprintf(stderr, "%s\n", strerror(errno));
 117                         sprintf(errmsg, "cannot seek temp file");
 118                         free(lp);
 119                         return NULL;
 120                 }
 121                 sfseek = ftell(sfp);
 122                 seek_write = 0;
 123         }
 124         /* assert: SPL1() */
 125         if ((ct = fwrite(cs, sizeof(char), len, sfp)) < 0 || ct != len) {
 126                 sfseek = -1;
 127                 fprintf(stderr, "%s\n", strerror(errno));
 128                 sprintf(errmsg, "cannot write temp file");
 129                 free(lp);
 130                 return NULL;
 131         }
 132         lp->len = len;
 133         lp->seek  = sfseek;
 134         add_line_node(lp);
 135         sfseek += len;                  /* update file position */
 136         return ++s;
 137 }
 138
 139
 140 /* add_line_node: add a line node in the editor buffer after the current line */
 141 void
 142 add_line_node(line_t *lp)
 143 {
 144         line_t *cp;
 145
 146         cp = get_addressed_line_node(current_addr); /* this get_addressed_line_node last! */
 147         INSQUE(lp, cp);
 148         addr_last++;
 149         current_addr++;
 150 }
 151
 152
 153 /* get_line_node_addr: return line number of pointer */
 154 long
 155 get_line_node_addr(line_t *lp)
 156 {
 157         line_t *cp = &buffer_head;
 158         long n = 0;
 159
 160         while (cp != lp && (cp = cp->q_forw) != &buffer_head)
 161                 n++;
 162         if (n && cp == &buffer_head) {
 163                 sprintf(errmsg, "invalid address");
 164                 return ERR;
 165         }
 166         return n;
 167 }
 168
 169
 170 /* get_addressed_line_node: return pointer to a line node in the editor buffer */
 171 line_t *
 172 get_addressed_line_node(long n)
 173 {
 174         static line_t *lp = &buffer_head;
 175         static long on = 0;
 176
 177         SPL1();
 178         if (n > on) {
 179                 if (n <= (on + addr_last) >> 1) {
 180                         for (; on < n; on++)
 181                                 lp = lp->q_forw;
 182                 } else {
 183                         lp = buffer_head.q_back;
 184                         for (on = addr_last; on > n; on--)
 185                                 lp = lp->q_back;
 186                 }
 187         } else {
 188                 if (n >= on >> 1) {
 189                         for (; on > n; on--)
 190                                 lp = lp->q_back;
 191                 } else {
 192                         lp = &buffer_head;
 193                         for (on = 0; on < n; on++)
 194                                 lp = lp->q_forw;
 195                 }
 196         }
 197         SPL0();
 198         return lp;
 199 }
 200
 201
 202 char *sfn = NULL;                               /* scratch file name */
 203
 204 /* open_sbuf: open scratch file */
 205 int
 206 open_sbuf(void)
 207 {
 208         int u, fd;
 209         const char *tmp;
 210         size_t s;
 211
 212         isbinary = newline_added = 0;
 213         fd = -1;
 214         u = umask(077);
 215
 216         if ((tmp = getenv("TMPDIR")) == NULL)
 217                 tmp = _PATH_TMP;
 218
 219         if ((s = strlen(tmp)) == 0 || tmp[s - 1] == '/')
 220                 (void)asprintf(&sfn, "%sed.XXXXXX", tmp);
 221         else
 222                 (void)asprintf(&sfn, "%s/ed.XXXXXX", tmp);
 223         if (sfn == NULL) {
 224                 warn(NULL);
 225                 sprintf(errmsg, "could not allocate memory");
 226                 umask(u);
 227                 return ERR;
 228         }
 229
 230
 231         if ((fd = mkstemp(sfn)) == -1 || (sfp = fdopen(fd, "w+")) == NULL) {
 232                 if (fd != -1)
 233                         close(fd);
 234                 warn("%s", sfn);
 235                 sprintf(errmsg, "cannot open temp file");
 236                 umask(u);
 237                 return ERR;
 238         }
 239         umask(u);
 240         return 0;
 241 }
 242
 243
 244 /* close_sbuf: close scratch file */
 245 int
 246 close_sbuf(void)
 247 {
 248         if (sfp) {
 249                 if (fclose(sfp) < 0) {
 250                         fprintf(stderr, "%s: %s\n", sfn, strerror(errno));
 251                         sprintf(errmsg, "cannot close temp file");
 252                         return ERR;
 253                 }
 254                 sfp = NULL;
 255                 if (sfn) {
 256                         unlink(sfn);
 257                         free(sfn);
 258                         sfn = NULL;
 259                 }
 260         }
 261         sfseek = seek_write = 0;
 262         return 0;
 263 }
 264
 265
 266 /* quit: remove_lines scratch file and exit */
 267 void
 268 quit(int n)
 269 {
 270         if (sfp) {
 271                 fclose(sfp);
 272                 if (sfn) {
 273                         unlink(sfn);
 274                         free(sfn);
 275                         sfn = NULL;
 276                 }
 277         }
 278         exit(n);
 279         /* NOTREACHED */
 280 }
 281
 282
 283 unsigned char ctab[256];                /* character translation table */
 284
 285 /* init_buffers: open scratch buffer; initialize line queue */
 286 void
 287 init_buffers(void)
 288 {
 289         int i = 0;
 290
 291         /* Read stdin one character at a time to avoid i/o contention
 292            with shell escapes invoked by nonterminal input, e.g.,
 293            ed - <<EOF
 294            !cat
 295            hello, world
 296            EOF */
 297         setbuffer(stdin, stdinbuf, 1);
 298         if (open_sbuf() < 0)
 299                 quit(2);
 300         REQUE(&buffer_head, &buffer_head);
 301         for (i = 0; i < 256; i++)
 302                 ctab[i] = i;
 303 }
 304
 305
 306 /* translit_text: translate characters in a string */
 307 char *
 308 translit_text(char *s, int len, int from, int to)
 309 {
 310         static int i = 0;
 311
 312         unsigned char *us;
 313
 314         ctab[i] = i;                    /* restore table to initial state */
 315         ctab[i = from] = to;
 316         for (us = (unsigned char *) s; len-- > 0; us++)
 317                 *us = ctab[*us];
 318         return s;
 319 }