root/libutil/fileop.c

/* */

DEFINITIONS

1. open_input_file
2. open_output_file
3. get_descripter
4. close_file

   1 /*
   2  * Copyright (c) 2006
   3  *      Tama Communications Corporation
   4  *
   5  * This file is part of GNU GLOBAL.
   6  *
   7  * This program is free software: you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation, either version 3 of the License, or
  10  * (at your option) any later version.
  11  * 
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  * 
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20 
  21 #ifdef HAVE_CONFIG_H
  22 #include <config.h>
  23 #endif
  24 #include <stdio.h>
  25 #ifdef STDC_HEADERS
  26 #include <stdlib.h>
  27 #endif
  28 
  29 #include "checkalloc.h"
  30 #include "die.h"
  31 #include "fileop.h"
  32 #include "makepath.h"
  33 #include "strlimcpy.h"
  34 
  35 /**
  36  @file
  37 
  38 File operation: usage
  39 
  40  @par [WRITE]
  41  @code
  42         int compress = cflag ? 1 : 0;
  43 
  44         FILEOP *fileop = open_output_file(path, compress);
  45         FILE *op = get_descripter(fileop);
  46 
  47         fputs("Hello", op);
  48         ...
  49         close_file(fileop);
  50  @endcode
  51 
  52  @par [READ]
  53  @code
  54         FILEOP *fileop = open_input_file(path);
  55         FILE *ip = get_descripter(fileop);
  56 
  57         fgets(buf, sizeof(buf), ip);
  58         ...
  59         close_file(fileop);
  60  @endcode
  61 */
  62 /**
  63  * open input file.
  64  *
  65  *      @param[in]      path    path name
  66  *      @return         file descripter
  67  */
  68 FILEOP *
  69 open_input_file(const char *path)
  70 {
  71         FILE *fp = fopen(path, "r");
  72         FILEOP *fileop;
  73 
  74         if (fp == NULL)
  75                 die("cannot open file '%s'.", path);
  76         fileop = check_calloc(sizeof(FILEOP), 1);
  77         fileop->fp = fp;
  78         strlimcpy(fileop->path, path, sizeof(fileop->path));
  79         fileop->type = FILEOP_INPUT;
  80         return fileop;
  81 }
  82 /**
  83  * open output file
  84  *
  85  *      @param[in]      path    path name
  86  *      @param[in]      compress 0: normal, 1: compress
  87  *      @return         file descripter
  88  *
  89  *      @note Uses the @NAME{gzip} program to compress, which should already be on your system.
  90  */
  91 FILEOP *
  92 open_output_file(const char *path, int compress)
  93 {
  94         FILEOP *fileop;
  95         FILE *fp;
  96         char command[MAXFILLEN];
  97 
  98         if (compress) {
  99                 snprintf(command, sizeof(command), "gzip -c >\"%s\"", path);
 100                 fp = popen(command, "w");
 101                 if (fp == NULL)
 102                         die("cannot create pipe.");
 103         } else {
 104                 fp = fopen(path, "w");
 105                 if (fp == NULL)
 106                         die("cannot create file '%s'.", path);
 107         }
 108         fileop = check_calloc(sizeof(FILEOP), 1);
 109         strlimcpy(fileop->path, path, sizeof(fileop->path));
 110         if (compress)
 111                 strlimcpy(fileop->command, command, sizeof(fileop->command));
 112         fileop->type = FILEOP_OUTPUT;
 113         if (compress)
 114                 fileop->type |= FILEOP_COMPRESS;
 115         fileop->fp = fp;
 116         return fileop;
 117 }
 118 /**
 119  * get UNIX file descripter
 120  *
 121  * ( See open_input_file() and open_output_file() ).
 122  */
 123 FILE *
 124 get_descripter(FILEOP *fileop)
 125 {
 126         return fileop->fp;
 127 }
 128 /**
 129  * close_file: close file
 130  *
 131  *      @param[in]      fileop  file descripter
 132  */
 133 void
 134 close_file(FILEOP *fileop)
 135 {
 136         if (fileop->type & FILEOP_COMPRESS) {
 137                 if (pclose(fileop->fp) != 0)
 138                         die("terminated abnormally. '%s'", fileop->command);
 139         } else
 140                 fclose(fileop->fp);
 141         free(fileop);
 142 }

/* */