pico/fileio.c

   1 #if     !defined(lint) && !defined(DOS)
   2 static char rcsid[] = "$Id: fileio.c 769 2007-10-24 00:15:40Z hubert@u.washington.edu $";
   3 #endif
   4
   5 /*
   6  * ========================================================================
   7  * Copyright 2006 University of Washington
   8  *
   9  * Licensed under the Apache License, Version 2.0 (the "License");
  10  * you may not use this file except in compliance with the License.
  11  * You may obtain a copy of the License at
  12  *
  13  *     http://www.apache.org/licenses/LICENSE-2.0
  14  *
  15  * ========================================================================
  16  *
  17  * Program:     file reading routines
  18  *
  19  */
  20
  21 /*
  22  * The routines in this file read and write ASCII files from the disk. All of
  23  * the knowledge about files are here. A better message writing scheme should
  24  * be used.
  25  */
  26 #include        "headers.h"
  27 #include        "../pith/charconv/filesys.h"
  28
  29
  30 #if     defined(bsd) || defined(lnx)
  31 extern int errno;
  32 #endif
  33
  34
  35
  36 FIOINFO g_pico_fio;
  37
  38 /*
  39  * Open a file for reading.
  40  */
  41 int
  42 ffropen(char *fn)
  43 {
  44     int status;
  45
  46     if ((status = fexist(g_pico_fio.name = fn, "r", (off_t *)NULL)) == FIOSUC){
  47         g_pico_fio.flags = FIOINFO_READ;
  48         if((g_pico_fio.fp = our_fopen(g_pico_fio.name, "r")) == NULL)
  49           status = FIOFNF;
  50     }
  51
  52     return (status);
  53 }
  54
  55
  56 /*
  57  * Write a line to the already opened file. The "buf" points to the buffer,
  58  * and the "nbuf" is its length, less the free newline. Return the status.
  59  * Check only at the newline.
  60  */
  61 int
  62 ffputline(CELL buf[], int nbuf)
  63 {
  64     register int    i;
  65     EML eml;
  66
  67     for(i = 0; i < nbuf; ++i)
  68        if(write_a_wide_char((UCS) buf[i].c, g_pico_fio.fp) == EOF)
  69          break;
  70
  71    if(i == nbuf)
  72      write_a_wide_char((UCS) '\n', g_pico_fio.fp);
  73
  74     if(ferror(g_pico_fio.fp)){
  75         eml.s = errstr(errno);
  76         emlwrite("\007Write error: %s", &eml);
  77         sleep(5);
  78         return FIOERR;
  79     }
  80
  81     return FIOSUC;
  82 }
  83
  84
  85 /*
  86  * Read a line from a file, and store the bytes in the supplied buffer. The
  87  * "nbuf" is the length of the buffer. Complain about long lines and lines
  88  * at the end of the file that don't have a newline present. Check for I/O
  89  * errors too. Return status.
  90  *
  91  * Translate the line from the user's locale charset to UCS-4.
  92  */
  93 int
  94 ffgetline(UCS buf[], size_t nbuf, size_t *charsreturned, int msg)
  95 {
  96     size_t i;
  97     UCS    ucs;
  98     static int displayed = 0;
  99
 100     if(charsreturned)
 101       *charsreturned = 0;
 102
 103     i = 0;
 104
 105     while((ucs = read_a_wide_char(g_pico_fio.fp, input_cs)) != CCONV_EOF && ucs != '\n'){
 106         /*
 107          * Don't blat the CR should the newline be CRLF and we're
 108          * running on a unix system.  NOTE: this takes care of itself
 109          * under DOS since the non-binary open turns newlines into '\n'.
 110          */
 111         if(ucs == '\r'){
 112             if((ucs = read_a_wide_char(g_pico_fio.fp, input_cs)) == CCONV_EOF || ucs == '\n')
 113               break;
 114
 115             if(i < nbuf-2)              /* Bare CR. Insert it and go on... */
 116               buf[i++] = '\r';          /* else, we're up a creek */
 117         }
 118
 119         if(i >= nbuf-2){
 120             buf[nbuf - 2] = ucs;        /* store last char read */
 121             buf[nbuf - 1] = '\0';       /* and terminate it */
 122             if(charsreturned)
 123               *charsreturned = nbuf - 1;
 124
 125             if(msg && displayed == 0){
 126               emlwrite("File has long line", NULL);
 127               displayed = 1;
 128             }
 129
 130             return FIOLNG;
 131         }
 132
 133         buf[i++] = ucs;
 134     }
 135
 136     if(ucs == CCONV_EOF){
 137         if(ferror(g_pico_fio.fp)){
 138             emlwrite("File read error", NULL);
 139             if(charsreturned)
 140               *charsreturned = i;
 141
 142             return FIOERR;
 143         }
 144
 145         if(i != 0)
 146           emlwrite("File doesn't end with newline.  Adding one.", NULL);
 147         else{
 148             if(charsreturned)
 149               *charsreturned = i;
 150             return FIOEOF;
 151         }
 152     }
 153
 154     buf[i] = '\0';
 155
 156     if(charsreturned)
 157       *charsreturned = i;
 158
 159     return FIOSUC;
 160 }