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 searched using the right extension order.
  67  *
  68  *    20-Apr-1999 (Eric Kohl <ekohl@abo.rhein-zeitung.de>)
  69  *        Some minor changes and improvements.
  70  */
  71
  72 #include "config.h"
  73
  74 #include <windows.h>
  75 #include <string.h>
  76 #include <stdlib.h>
  77
  78 #include "cmd.h"
  79
  80
  81 /* initial size of environment variable buffer */
  82 #define ENV_BUFFER_SIZE  1024
  83
  84
  85 static LPTSTR ext[]  = {".bat", ".cmd", ".com", ".exe"};
  86 static INT nExtCount = sizeof(ext) / sizeof(LPTSTR);
  87
  88
  89 /* searches for file using path info. */
  90
  91 BOOL
  92 SearchForExecutable (LPCTSTR pFileName, LPTSTR pFullName)
  93 {
  94         TCHAR  szPathBuffer[MAX_PATH];
  95         LPTSTR pszBuffer = NULL;
  96         DWORD  dwBuffer, len;
  97         INT    n;
  98         LPTSTR p,s,f;
  99
 100         /* load environment varable PATH into buffer */
 101         pszBuffer = (LPTSTR)malloc (ENV_BUFFER_SIZE * sizeof(TCHAR));
 102         dwBuffer = GetEnvironmentVariable (_T("PATH"), pszBuffer, ENV_BUFFER_SIZE);
 103         if (dwBuffer > ENV_BUFFER_SIZE)
 104         {
 105                 pszBuffer = (LPTSTR)realloc (pszBuffer, dwBuffer * sizeof (TCHAR));
 106                 GetEnvironmentVariable (_T("PATH"), pszBuffer, dwBuffer * sizeof (TCHAR));
 107         }
 108
 109         /* initialize full name buffer */
 110         *pFullName = _T('\0');
 111
 112         if (!(p = _tcsrchr (pFileName, _T('.'))) ||
 113                 _tcschr (p + 1, _T('\\')))
 114         {
 115                 /* There is no extension ==> test all the extensions. */
 116 #ifdef _DEBUG
 117                 DebugPrintf (_T("No filename extension!\n"));
 118 #endif
 119
 120                 /* search in current directory */
 121                 len = GetCurrentDirectory (MAX_PATH, szPathBuffer);
 122                 if (szPathBuffer[len - 1] != _T('\\'))
 123                 {
 124                         szPathBuffer[len] = _T('\\');
 125                         szPathBuffer[len + 1] = _T('\0');
 126                 }
 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                         len = _tcslen(szPathBuffer);
 169                         if (szPathBuffer[len - 1] != _T('\\'))
 170                         {
 171                                 szPathBuffer[len] = _T('\\');
 172                                 szPathBuffer[len + 1] = _T('\0');
 173                         }
 174                         _tcscat (szPathBuffer, pFileName);
 175
 176                         p = szPathBuffer + _tcslen (szPathBuffer);
 177
 178                         for (n = 0; n < nExtCount; n++)
 179                         {
 180                                 _tcscpy (p, ext[n]);
 181
 182 #ifdef _DEBUG
 183                                 DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 184 #endif
 185
 186                                 if (IsValidFileName (szPathBuffer))
 187                                 {
 188 #ifdef _DEBUG
 189                                         DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 190 #endif
 191                                         free (pszBuffer);
 192                                         _tcscpy (pFullName, szPathBuffer);
 193                                         return TRUE;
 194                                 }
 195                         }
 196                 }
 197         }
 198         else
 199         {
 200                 /* There is an extension and it is in the last path component, */
 201                 /* so don't test all the extensions. */
 202 #ifdef _DEBUG
 203                 DebugPrintf (_T("Filename extension!\n"));
 204 #endif
 205
 206                 /* search in current directory */
 207                 len = GetCurrentDirectory (MAX_PATH, szPathBuffer);
 208                 if (szPathBuffer[len - 1] != _T('\\'))
 209                 {
 210                         szPathBuffer[len] = _T('\\');
 211                         szPathBuffer[len + 1] = _T('\0');
 212                 }
 213                 _tcscat (szPathBuffer, pFileName);
 214
 215 #ifdef _DEBUG
 216                 DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 217 #endif
 218                 if (IsValidFileName (szPathBuffer))
 219                 {
 220 #ifdef _DEBUG
 221                         DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 222 #endif
 223                         free (pszBuffer);
 224                         _tcscpy (pFullName, szPathBuffer);
 225                         return TRUE;
 226                 }
 227
 228
 229                 /* search in PATH */
 230                 s = pszBuffer;
 231                 while (s && *s)
 232                 {
 233                         f = _tcschr (s, _T(';'));
 234
 235                         if (f)
 236                         {
 237                                 _tcsncpy (szPathBuffer, s, (size_t)(f-s));
 238                                 szPathBuffer[f-s] = _T('\0');
 239                                 s = f + 1;
 240                         }
 241                         else
 242                         {
 243                                 _tcscpy (szPathBuffer, s);
 244                                 s = NULL;
 245                         }
 246
 247                         len = _tcslen(szPathBuffer);
 248                         if (szPathBuffer[len - 1] != _T('\\'))
 249                         {
 250                                 szPathBuffer[len] = _T('\\');
 251                                 szPathBuffer[len + 1] = _T('\0');
 252                         }
 253                         _tcscat (szPathBuffer, pFileName);
 254
 255 #ifdef _DEBUG
 256                         DebugPrintf (_T("Testing: \'%s\'\n"), szPathBuffer);
 257 #endif
 258                         if (IsValidFileName (szPathBuffer))
 259                         {
 260 #ifdef _DEBUG
 261                                 DebugPrintf (_T("Found: \'%s\'\n"), szPathBuffer);
 262 #endif
 263                                 free (pszBuffer);
 264                                 _tcscpy (pFullName, szPathBuffer);
 265                                 return TRUE;
 266                         }
 267                 }
 268         }
 269
 270         free (pszBuffer);
 271
 272         return FALSE;
 273 }