OSX/libsecurity_cdsa_utils/lib/cuFileIo.c

   1 /*
   2  * Copyright (c) 2001-2003,2011-2012,2014 Apple Inc. All Rights Reserved.
   3  *
   4  * The contents of this file constitute Original Code as defined in and are
   5  * subject to the Apple Public Source License Version 1.2 (the 'License').
   6  * You may not use this file except in compliance with the License. Please
   7  * obtain a copy of the License at http://www.apple.com/publicsource and
   8  * read it before using this file.
   9  *
  10  * This Original Code and all software distributed under the License are
  11  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  12  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  13  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  14  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  15  * Please see the License for the specific language governing rights and
  16  * limitations under the License.
  17  */
  18
  19 /*
  20         File:            cuFileIo.c
  21
  22         Description: simple file read/write utilities
  23 */
  24
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <errno.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32 #include "cuFileIo.h"
  33
  34 int writeFile(
  35               const char                        *fileName,
  36               const unsigned char       *bytes,
  37               unsigned              numBytes)
  38 {
  39     size_t n = numBytes;
  40     return writeFileSizet(fileName, bytes, n);
  41 }
  42
  43 int writeFileSizet(
  44         const char                      *fileName,
  45         const unsigned char     *bytes,
  46         size_t                  numBytes)
  47 {
  48         int             rtn;
  49         int     fd;
  50
  51         fd = open(fileName, O_RDWR | O_CREAT | O_TRUNC, 0600);
  52     if(fd == -1) {
  53                 return errno;
  54         }
  55         rtn = (int)write(fd, bytes, (size_t)numBytes);
  56         if(rtn != (int)numBytes) {
  57                 if(rtn >= 0) {
  58                         printf("writeFile: short write\n");
  59                 }
  60                 rtn = EIO;
  61         }
  62         else {
  63                 rtn = 0;
  64         }
  65         close(fd);
  66         return rtn;
  67 }
  68
  69 /*
  70  * Read entire file.
  71  */
  72 int readFile(
  73         const char              *fileName,
  74         unsigned char   **bytes,                // mallocd and returned
  75         unsigned                *numBytes)              // returned
  76 {
  77         int rtn;
  78         int fd;
  79         unsigned char *buf;
  80         struct stat     sb;
  81         unsigned size;
  82
  83         *numBytes = 0;
  84         *bytes = NULL;
  85         fd = open(fileName, O_RDONLY, 0);
  86     if(fd == -1) {
  87                 return errno;
  88         }
  89         rtn = fstat(fd, &sb);
  90         if(rtn) {
  91                 goto errOut;
  92         }
  93         size = (unsigned)sb.st_size;
  94         buf = malloc(size);
  95         if(buf == NULL) {
  96                 rtn = ENOMEM;
  97                 goto errOut;
  98         }
  99         rtn = (int)lseek(fd, 0, SEEK_SET);
 100         if(rtn < 0) {
 101                 free(buf);
 102                 goto errOut;
 103         }
 104         rtn = (int)read(fd, buf, (size_t)size);
 105         if(rtn != (int)size) {
 106                 if(rtn >= 0) {
 107                         printf("readFile: short read\n");
 108                 }
 109                 free(buf);
 110                 rtn = EIO;
 111         }
 112         else {
 113                 rtn = 0;
 114                 *bytes = buf;
 115                 *numBytes = size;
 116         }
 117 errOut:
 118         close(fd);
 119         return rtn;
 120 }