reactos/base/shell/cmd/dirstack.c
Hermès Bélusca-Maïto 3f892a8d6b
[CMD] Add missing memory allocation NULL checks (#161). CORE-8304
Adapted from a patch by Jacob S. Preciado.

Bring also the code suggestions emitted during review.
2018-08-21 14:02:24 +02:00

184 lines
2.8 KiB
C

/*
* DIRSTACK.C - pushd / pop (directory stack) internal commands.
*
*
* History:
*
* 14-Dec-1998 (Eric Kohl)
* Implemented PUSHD and POPD command.
*
* 20-Jan-1999 (Eric Kohl)
* Unicode and redirection safe!
*
* 20-Jan-1999 (Eric Kohl)
* Added DIRS command.
*/
#include "precomp.h"
#ifdef FEATURE_DIRECTORY_STACK
typedef struct tagDIRENTRY
{
struct tagDIRENTRY *prev;
struct tagDIRENTRY *next;
TCHAR szPath[1];
} DIRENTRY, *LPDIRENTRY;
static INT nStackDepth;
static LPDIRENTRY lpStackTop;
static LPDIRENTRY lpStackBottom;
static INT
PushDirectory (LPTSTR pszPath)
{
LPDIRENTRY lpDir = cmd_alloc(FIELD_OFFSET(DIRENTRY, szPath[_tcslen(pszPath) + 1]));
if (!lpDir)
{
WARN("Cannot allocate memory for lpDir\n");
error_out_of_memory();
return -1;
}
lpDir->prev = NULL;
lpDir->next = lpStackTop;
if (lpStackTop == NULL)
lpStackBottom = lpDir;
else
lpStackTop->prev = lpDir;
lpStackTop = lpDir;
_tcscpy(lpDir->szPath, pszPath);
nStackDepth++;
return nErrorLevel = 0;
}
static VOID
PopDirectory (VOID)
{
LPDIRENTRY lpDir = lpStackTop;
lpStackTop = lpDir->next;
if (lpStackTop != NULL)
lpStackTop->prev = NULL;
else
lpStackBottom = NULL;
cmd_free (lpDir);
nStackDepth--;
}
/*
* initialize directory stack
*/
VOID InitDirectoryStack (VOID)
{
nStackDepth = 0;
lpStackTop = NULL;
lpStackBottom = NULL;
}
/*
* destroy directory stack
*/
VOID DestroyDirectoryStack (VOID)
{
while (nStackDepth)
PopDirectory ();
}
INT GetDirectoryStackDepth (VOID)
{
return nStackDepth;
}
/*
* pushd command
*/
INT CommandPushd (LPTSTR rest)
{
TCHAR curPath[MAX_PATH];
if (!_tcsncmp (rest, _T("/?"), 2))
{
ConOutResPuts(STRING_DIRSTACK_HELP1);
return 0;
}
GetCurrentDirectory (MAX_PATH, curPath);
if (rest[0] != _T('\0'))
{
if (!SetRootPath(NULL, rest))
return 1;
}
return PushDirectory(curPath);
}
/*
* popd command
*/
INT CommandPopd (LPTSTR rest)
{
INT ret = 0;
if (!_tcsncmp(rest, _T("/?"), 2))
{
ConOutResPuts(STRING_DIRSTACK_HELP2);
return 0;
}
if (nStackDepth == 0)
return 1;
ret = _tchdir(lpStackTop->szPath) != 0;
PopDirectory ();
return ret;
}
/*
* dirs command
*/
INT CommandDirs (LPTSTR rest)
{
LPDIRENTRY lpDir;
if (!_tcsncmp(rest, _T("/?"), 2))
{
ConOutResPuts(STRING_DIRSTACK_HELP3);
return 0;
}
nErrorLevel = 0;
lpDir = lpStackBottom;
if (lpDir == NULL)
{
ConOutResPuts(STRING_DIRSTACK_HELP4);
return 0;
}
while (lpDir != NULL)
{
ConOutPuts(lpDir->szPath);
lpDir = lpDir->prev;
}
return 0;
}
#endif /* FEATURE_DIRECTORY_STACK */