wmmenu/utils.c

   1 #define _POSIX_SOURCE
   2 #define _POSIX_C_SOURCE 199309L
   3
   4 #include <stdio.h>
   5 #include <stdlib.h>
   6 #include <string.h>
   7 #include <errno.h>
   8 #include <assert.h>
   9 /* POSIX */
  10 #include <unistd.h>
  11
  12 #include "utils.h"
  13 #include "error.h"
  14 #include "types.h"
  15
  16 static char * ReadAll (FILE * f, int offset)
  17 {
  18     char buf [10*1024] ;
  19     size_t iRead, nRead ;
  20     char * ret ;
  21
  22     clearerr (f) ;
  23
  24     iRead = 0 ;
  25     nRead = 0 ;
  26     while (iRead < sizeof buf)
  27     {
  28         nRead = fread (buf+iRead, 1, (sizeof buf)-iRead, f) ;
  29         if (nRead <= 0) break ;
  30         iRead += nRead ;
  31     }
  32
  33     if (nRead > 0)
  34     {
  35         assert (iRead == sizeof buf) ;
  36         ret = ReadAll (f, offset+iRead) ;
  37     }
  38     else
  39     if (ferror (f) != 0)
  40     {
  41         error ("read file: %s", strerror (errno)) ;
  42         ret = NULL ;
  43     }
  44     else
  45     {
  46         ret = malloc (offset+iRead+1) ;
  47         if (ret == NULL) error ("failed to allocate memory") ;
  48         ret[offset+iRead] = EOS ;
  49     }
  50     memcpy (ret+offset, buf, iRead) ;
  51
  52     return ret ;
  53 }
  54
  55 extern char * File_ReadAll (FILE * f)
  56 {
  57     assert (f != NULL) ;
  58     return ReadAll (f, 0) ;
  59 }
  60
  61 static const char * getHome (void)
  62 {
  63     static char homeDir [80] = "" ;
  64     static int initialized = 0 ;
  65     if (! initialized)
  66     {
  67         const char * env ;
  68         env = getenv ("HOME") ;
  69         if (env != NULL && env[0] != EOS)
  70         {
  71             sprintf (homeDir, "%.*s", (int)(sizeof homeDir)-1, env) ;
  72         }
  73         initialized = 1 ;
  74     }
  75     return homeDir[0] != EOS ? homeDir : NULL ;
  76 }
  77
  78 extern bool File_FindInPath (char * out, int outSz,
  79     const char * path, const char * basename)
  80 {
  81     char name [FILENAME_MAX] ;
  82     int len ;
  83
  84     assert (path != NULL) ;
  85     assert (basename != NULL) ;
  86     assert (out != NULL) ;
  87
  88     /* regular path */
  89     if (access (basename, F_OK) == 0)
  90     {
  91         sprintf (out, "%.*s", outSz-1, basename) ;
  92         return true ;
  93     }
  94     else
  95     /* relative to home directory */
  96     if (strncmp (basename, "~/", 2) == 0 && getHome () != NULL)
  97     {
  98         sprintf (name, "%s%s", getHome (), basename+1) ;
  99         if (access (name, F_OK) == 0)
 100         {
 101             sprintf (out, "%.*s", outSz-1, name) ;
 102             return true ;
 103         }
 104         else
 105         {
 106             return false ;
 107         }
 108     }
 109     else
 110     /* forbid relative to PATH just like shell */
 111     /* NB: absolute non-existent files also drop here */
 112     if (strchr (basename, '/') != NULL)
 113     {
 114         return false ;
 115     }
 116     else
 117     {
 118         while (*path != EOS)
 119         {
 120             len = strcspn (path, ":") ;
 121
 122             if (strncmp (path, "~/", 2) == 0)
 123             {
 124                 sprintf (name, "%s%.*s/%s",
 125                     getHome (), len-1, path+1, basename) ;
 126             }
 127             else
 128             {
 129                 sprintf (name, "%.*s/%s", len, path, basename) ;
 130             }
 131
 132             if (access (name, F_OK) == 0)
 133             {
 134                 sprintf (out, "%.*s", outSz-1, name) ;
 135                 return true ;
 136             }
 137
 138             path += len ;
 139             while (*path == ':') path++ ;
 140         }
 141
 142         return false ;
 143     }
 144 }
 145
 146 extern char * File_ReadOutputFromCommand (const char * cmd)
 147 {
 148     FILE * out ;
 149     char * ret ;
 150
 151     if ((out = popen (cmd, "r")) == NULL)
 152     {
 153         error ("when calling command: %s, error: ",
 154             cmd, strerror (errno)) ;
 155         ret = NULL ;
 156     }
 157     else
 158     {
 159         ret = File_ReadAll (out) ;
 160         pclose (out) ;
 161
 162         /* if return value is correct, remove trailing whitespace */
 163         if (ret != NULL)
 164         {
 165             char *lastNotWhite, *cursor ;
 166             char c ;
 167
 168             cursor = lastNotWhite = ret ;
 169
 170             while ((c = *cursor++) != EOS)
 171             {
 172                 if (strchr (" \t\n", c) == NULL)
 173                 {
 174                     lastNotWhite = cursor ;
 175                 }
 176             }
 177
 178             *lastNotWhite = EOS ;
 179         }
 180     }
 181
 182     return ret ;
 183 }