rosapps/cmd/where.c

   1 /*
   2  *  WHERE.C - file search functions.
   3  *
   4  *
   5  *  History:
   6  *
   7  *    07/15/95 (Tim Norman)
   8  *        started.
   9  *
  10  *    08/08/95 (Matt Rains)
  11  *        i have cleaned up the source code. changes now bring this source
  12  *        into guidelines for recommended programming practice.
  13  *
  14  *    12/12/95 (Steffan Kaiser & Tim Norman)
  15  *        added some patches to fix some things and make more efficient
  16  *
  17  *    1/6/96 (Tim Norman)
  18  *        fixed a stupid pointer mistake...
  19  *        Thanks to everyone who noticed it!
  20  *
  21  *    8/1/96 (Tim Norman)
  22  *        fixed a bug when getenv returns NULL
  23  *
  24  *    8/7/96 (Steffan Kaiser and Tim Norman)
  25  *        speed improvements and bug fixes
  26  *
  27  *    8/27/96 (Tim Norman)
  28  *        changed code to use pointers directly into PATH environment
  29  *        variable rather than making our own copy.  This saves some memory,
  30  *        but requires we write our own function to copy pathnames out of
  31  *        the variable.
  32  *
  33  *    12/23/96 (Aaron Kaufman)
  34  *        Fixed a bug in get_paths() that did not point to the first PATH
  35  *        in the environment variable.
  36  *
  37  *    7/12/97 (Tim Norman)
  38  *        Apparently, Aaron's bugfix got lost, so I fixed it again.
  39  *
  40  *    16 July 1998 (John P. Price)
  41  *        Added stand alone code.
  42  *
  43  *    17 July 1998 (John P. Price)
  44  *        Rewrote find_which to use searchpath function
  45  *
  46  *    24-Jul-1998 (John P Price <linux-guru@gcfl.net>)
  47  *        fixed bug where didn't check all extensions when path was specified
  48  *
  49  *    27-Jul-1998 (John P Price <linux-guru@gcfl.net>)
  50  *        added config.h include
  51  *
  52  *    30-Jul-1998 (John P Price <linux-guru@gcfl.net>)
  53  *        fixed so that it find_which returns NULL if filename is not
  54  *        executable (does not have .bat, .com, or .exe extention).
  55  *        Before command would to execute any file with any extension (opps!)
  56  *
  57  *    03-Dec-1998 (Eric Kohl <ekohl@abo.rhein-zeitung.de>)
  58  *        Changed find_which().
  59  *
  60  *    07-Dec-1998 (Eric Kohl <ekohl@abo.rhein-zeitung.de>)
  61  *        Added ".CMD" extension.
  62  *        Replaced numeric constant by _NR_OF_EXTENSIONS.
  63  *
  64  *    26-Feb-1999 (Eric Kohl <ekohl@abo.rhein-zeitung.de>)
  65  *        Replaced find_which() by SearchForExecutable().
  66  *        Now files are serched with the right order of extensions.
  67  */
  68
  69 #include "config.h"
  70
  71 #include <windows.h>
  72 #include <string.h>
  73 #include <stdlib.h>
  74
  75 #include "cmd.h"
  76
  77
  78 /* initial size of environment variable buffer */
  79 #define ENV_BUFFER_SIZE  1024
  80
  81
  82 static LPTSTR ext[]  = {".BAT", ".CMD", ".COM", ".EXE"};
  83 static INT nExtCount = sizeof(ext) / sizeof(LPTSTR);
  84
  85
  86 /* searches for file using path info. */
  87
  88 BOOL
  89 SearchForExecutable (LPCTSTR pFileName, LPTSTR pFullName)
  90 {
  91         TCHAR  szPathBuffer[MAX_PATH];
  92         LPTSTR pszBuffer;
  93         DWORD  dwBuffer;
  94         INT    n;
  95         LPTSTR p,s,f;
  96
  97         /* load environment varable PATH into buffer */
  98         pszBuffer = (LPTSTR)malloc (ENV_BUFFER_SIZE * sizeof(TCHAR));
  99         dwBuffer = GetEnvironmentVariable (_T("PATH"), pszBuffer, ENV_BUFFER_SIZE);
 100         if (dwBuffer == 0)
 101         {
 102                 ConErrPrintf (_T("Not PATH environment variable found!\n"));
 103                 return 0;
 104         }
 105         else if (dwBuffer > ENV_BUFFER_SIZE)
 106         {
 107                 pszBuffer = (LPTSTR)realloc (pszBuffer, dwBuffer * sizeof (TCHAR));
 108                 GetEnvironmentVariable (_T("PATH"), pszBuffer, dwBuffer * sizeof (TCHAR));
 109         }
 110
 111
 112         /* initialize full name buffer */
 113         *pFullName = _T('\0');
 114
 115         if (!(p = _tcsrchr (pFileName, _T('.'))) ||
 116                 _tcschr (p + 1, _T('\\')))
 117         {
 118                 /* There is no extension ==> test all the extensions. */
 119 #ifdef _DEBUG
 120                 DebugPrintf (_T("No filename extension!\n"));
 121 #endif
 122
 123                 /* search in current directory */
 124                 GetCurrentDirectory (MAX_PATH, szPathBuffer);
 125                 if (szPathBuffer[_tcslen(szPathBuffer)-1] != _T('\\'))
 126                         _tcscat (szPathBuffer, _T("\\"));
 127                 _tcscat (szPathBuffer, pFileName);
 128
 129                 p = szPathBuffer + _tcslen (szPathBuffer);
 130
 131                 for (n = 0; n < nExtCount; n++)
 132                 {
 133                         _tcscpy (p, ext[n]);
 134
 135 #ifdef _DEBUG
 136                         DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 137 #endif
 138
 139                         if (IsValidFileName (szPathBuffer))
 140                         {
 141 #ifdef _DEBUG
 142                                 DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 143 #endif
 144                                 free (pszBuffer);
 145                                 _tcscpy (pFullName, szPathBuffer);
 146                                 return TRUE;
 147                         }
 148                 }
 149
 150                 /* search in PATH */
 151                 s = pszBuffer;
 152                 while (s && *s)
 153                 {
 154                         f = _tcschr (s, _T(';'));
 155
 156                         if (f)
 157                         {
 158                                 _tcsncpy (szPathBuffer, s, (size_t)(f-s));
 159                                 szPathBuffer[f-s] = _T('\0');
 160                                 s = f + 1;
 161                         }
 162                         else
 163                         {
 164                                 _tcscpy (szPathBuffer, s);
 165                                 s = NULL;
 166                         }
 167
 168                         if (szPathBuffer[_tcslen(szPathBuffer)-1] != _T('\\'))
 169                                 _tcscat (szPathBuffer, _T("\\"));
 170                         _tcscat (szPathBuffer, pFileName);
 171
 172                         p = szPathBuffer + _tcslen (szPathBuffer);
 173
 174                         for (n = 0; n < nExtCount; n++)
 175                         {
 176                                 _tcscpy (p, ext[n]);
 177
 178 #ifdef _DEBUG
 179                                 DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 180 #endif
 181
 182                                 if (IsValidFileName (szPathBuffer))
 183                                 {
 184 #ifdef _DEBUG
 185                                         DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 186 #endif
 187                                         free (pszBuffer);
 188                                         _tcscpy (pFullName, szPathBuffer);
 189                                         return TRUE;
 190                                 }
 191                         }
 192                 }
 193         }
 194         else
 195         {
 196                 /* There is an extension and it is in the last path component, */
 197                 /* so don't test all the extensions. */
 198 #ifdef _DEBUG
 199                 DebugPrintf (_T("Filename extension!\n"));
 200 #endif
 201
 202                 /* search in current directory */
 203                 GetCurrentDirectory (MAX_PATH, szPathBuffer);
 204                 if (szPathBuffer[_tcslen(szPathBuffer)-1] != _T('\\'))
 205                         _tcscat (szPathBuffer, _T("\\"));
 206                 _tcscat (szPathBuffer, pFileName);
 207
 208 #ifdef _DEBUG
 209                 DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 210 #endif
 211                 if (IsValidFileName (szPathBuffer))
 212                 {
 213 #ifdef _DEBUG
 214                         DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 215 #endif
 216                         free (pszBuffer);
 217                         _tcscpy (pFullName, szPathBuffer);
 218                         return TRUE;
 219                 }
 220
 221
 222                 /* search in PATH */
 223                 s = pszBuffer;
 224                 while (s && *s)
 225                 {
 226                         f = _tcschr (s, _T(';'));
 227
 228                         if (f)
 229                         {
 230                                 _tcsncpy (szPathBuffer, s, (size_t)(f-s));
 231                                 szPathBuffer[f-s] = _T('\0');
 232                                 s = f + 1;
 233                         }
 234                         else
 235                         {
 236                                 _tcscpy (szPathBuffer, s);
 237                                 s = NULL;
 238                         }
 239
 240                         if (szPathBuffer[_tcslen(szPathBuffer)-1] != _T('\\'))
 241                                 _tcscat (szPathBuffer, _T("\\"));
 242                         _tcscat (szPathBuffer, pFileName);
 243
 244 #ifdef _DEBUG
 245                         DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 246 #endif
 247                         if (IsValidFileName (szPathBuffer))
 248                         {
 249 #ifdef _DEBUG
 250                                 DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 251 #endif
 252                                 free (pszBuffer);
 253                                 _tcscpy (pFullName, szPathBuffer);
 254                                 return TRUE;
 255                         }
 256                 }
 257         }
 258
 259         free (pszBuffer);
 260
 261         return FALSE;
 262 }