pico/fileio.c

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