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Diffstat (limited to 'dirent/include/dirent.h')
| -rw-r--r-- | dirent/include/dirent.h | 1212 |
1 files changed, 1212 insertions, 0 deletions
diff --git a/dirent/include/dirent.h b/dirent/include/dirent.h new file mode 100644 index 0000000..557485a --- /dev/null +++ b/dirent/include/dirent.h @@ -0,0 +1,1212 @@ +/* + * Dirent interface for Microsoft Visual Studio + * + * Copyright (C) 1998-2019 Toni Ronkko + * This file is part of dirent. Dirent may be freely distributed + * under the MIT license. For all details and documentation, see + * https://github.com/tronkko/dirent + */ +#ifndef DIRENT_H +#define DIRENT_H + +/* Hide warnings about unreferenced local functions */ +#if defined(__clang__) +# pragma clang diagnostic ignored "-Wunused-function" +#elif defined(_MSC_VER) +# pragma warning(disable:4505) +#elif defined(__GNUC__) +# pragma GCC diagnostic ignored "-Wunused-function" +#endif + +/* + * Include windows.h without Windows Sockets 1.1 to prevent conflicts with + * Windows Sockets 2.0. + */ +#ifndef WIN32_LEAN_AND_MEAN +# define WIN32_LEAN_AND_MEAN +#endif +#include <windows.h> + +#include <stdio.h> +#include <stdarg.h> +#include <wchar.h> +#include <string.h> +#include <stdlib.h> +#include <malloc.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <errno.h> +#include <ctype.h> + +/* Indicates that d_type field is available in dirent structure */ +#define _DIRENT_HAVE_D_TYPE + +/* Indicates that d_namlen field is available in dirent structure */ +#define _DIRENT_HAVE_D_NAMLEN + +/* Entries missing from MSVC 6.0 */ +#if !defined(FILE_ATTRIBUTE_DEVICE) +# define FILE_ATTRIBUTE_DEVICE 0x40 +#endif + +/* File type and permission flags for stat(), general mask */ +#if !defined(S_IFMT) +# define S_IFMT _S_IFMT +#endif + +/* Directory bit */ +#if !defined(S_IFDIR) +# define S_IFDIR _S_IFDIR +#endif + +/* Character device bit */ +#if !defined(S_IFCHR) +# define S_IFCHR _S_IFCHR +#endif + +/* Pipe bit */ +#if !defined(S_IFFIFO) +# define S_IFFIFO _S_IFFIFO +#endif + +/* Regular file bit */ +#if !defined(S_IFREG) +# define S_IFREG _S_IFREG +#endif + +/* Read permission */ +#if !defined(S_IREAD) +# define S_IREAD _S_IREAD +#endif + +/* Write permission */ +#if !defined(S_IWRITE) +# define S_IWRITE _S_IWRITE +#endif + +/* Execute permission */ +#if !defined(S_IEXEC) +# define S_IEXEC _S_IEXEC +#endif + +/* Pipe */ +#if !defined(S_IFIFO) +# define S_IFIFO _S_IFIFO +#endif + +/* Block device */ +#if !defined(S_IFBLK) +# define S_IFBLK 0 +#endif + +/* Link */ +#if !defined(S_IFLNK) +# define S_IFLNK 0 +#endif + +/* Socket */ +#if !defined(S_IFSOCK) +# define S_IFSOCK 0 +#endif + +/* Read user permission */ +#if !defined(S_IRUSR) +# define S_IRUSR S_IREAD +#endif + +/* Write user permission */ +#if !defined(S_IWUSR) +# define S_IWUSR S_IWRITE +#endif + +/* Execute user permission */ +#if !defined(S_IXUSR) +# define S_IXUSR 0 +#endif + +/* Read group permission */ +#if !defined(S_IRGRP) +# define S_IRGRP 0 +#endif + +/* Write group permission */ +#if !defined(S_IWGRP) +# define S_IWGRP 0 +#endif + +/* Execute group permission */ +#if !defined(S_IXGRP) +# define S_IXGRP 0 +#endif + +/* Read others permission */ +#if !defined(S_IROTH) +# define S_IROTH 0 +#endif + +/* Write others permission */ +#if !defined(S_IWOTH) +# define S_IWOTH 0 +#endif + +/* Execute others permission */ +#if !defined(S_IXOTH) +# define S_IXOTH 0 +#endif + +/* Maximum length of file name */ +#if !defined(PATH_MAX) +# define PATH_MAX MAX_PATH +#endif +#if !defined(FILENAME_MAX) +# define FILENAME_MAX MAX_PATH +#endif +#if !defined(NAME_MAX) +# define NAME_MAX FILENAME_MAX +#endif + +/* File type flags for d_type */ +#define DT_UNKNOWN 0 +#define DT_REG S_IFREG +#define DT_DIR S_IFDIR +#define DT_FIFO S_IFIFO +#define DT_SOCK S_IFSOCK +#define DT_CHR S_IFCHR +#define DT_BLK S_IFBLK +#define DT_LNK S_IFLNK + +/* Macros for converting between st_mode and d_type */ +#define IFTODT(mode) ((mode) & S_IFMT) +#define DTTOIF(type) (type) + +/* + * File type macros. Note that block devices, sockets and links cannot be + * distinguished on Windows and the macros S_ISBLK, S_ISSOCK and S_ISLNK are + * only defined for compatibility. These macros should always return false + * on Windows. + */ +#if !defined(S_ISFIFO) +# define S_ISFIFO(mode) (((mode) & S_IFMT) == S_IFIFO) +#endif +#if !defined(S_ISDIR) +# define S_ISDIR(mode) (((mode) & S_IFMT) == S_IFDIR) +#endif +#if !defined(S_ISREG) +# define S_ISREG(mode) (((mode) & S_IFMT) == S_IFREG) +#endif +#if !defined(S_ISLNK) +# define S_ISLNK(mode) (((mode) & S_IFMT) == S_IFLNK) +#endif +#if !defined(S_ISSOCK) +# define S_ISSOCK(mode) (((mode) & S_IFMT) == S_IFSOCK) +#endif +#if !defined(S_ISCHR) +# define S_ISCHR(mode) (((mode) & S_IFMT) == S_IFCHR) +#endif +#if !defined(S_ISBLK) +# define S_ISBLK(mode) (((mode) & S_IFMT) == S_IFBLK) +#endif + +/* Return the exact length of the file name without zero terminator */ +#define _D_EXACT_NAMLEN(p) ((p)->d_namlen) + +/* Return the maximum size of a file name */ +#define _D_ALLOC_NAMLEN(p) ((PATH_MAX)+1) + + +#ifdef __cplusplus +extern "C" { +#endif + + +/* Wide-character version */ +struct _wdirent { + /* Always zero */ + long d_ino; + + /* Position of next file in a directory stream */ + long d_off; + + /* Structure size */ + unsigned short d_reclen; + + /* Length of name without \0 */ + size_t d_namlen; + + /* File type */ + int d_type; + + /* File name */ + wchar_t d_name[PATH_MAX+1]; +}; +typedef struct _wdirent _wdirent; + +struct _WDIR { + /* Current directory entry */ + struct _wdirent ent; + + /* Private file data */ + WIN32_FIND_DATAW data; + + /* True if data is valid */ + int cached; + + /* True if next entry is invalid */ + int invalid; + + /* Win32 search handle */ + HANDLE handle; + + /* Initial directory name */ + wchar_t *patt; +}; +typedef struct _WDIR _WDIR; + +/* Multi-byte character version */ +struct dirent { + /* Always zero */ + long d_ino; + + /* Position of next file in a directory stream */ + long d_off; + + /* Structure size */ + unsigned short d_reclen; + + /* Length of name without \0 */ + size_t d_namlen; + + /* File type */ + int d_type; + + /* File name */ + char d_name[PATH_MAX+1]; +}; +typedef struct dirent dirent; + +struct DIR { + struct dirent ent; + struct _WDIR *wdirp; +}; +typedef struct DIR DIR; + + +/* Dirent functions */ +static DIR *opendir(const char *dirname); +static _WDIR *_wopendir(const wchar_t *dirname); + +static struct dirent *readdir(DIR *dirp); +static struct _wdirent *_wreaddir(_WDIR *dirp); + +static int readdir_r( + DIR *dirp, struct dirent *entry, struct dirent **result); +static int _wreaddir_r( + _WDIR *dirp, struct _wdirent *entry, struct _wdirent **result); + +static int closedir(DIR *dirp); +static int _wclosedir(_WDIR *dirp); + +static void rewinddir(DIR *dirp); +static void _wrewinddir(_WDIR *dirp); + +static long telldir(DIR *dirp); +static long _wtelldir(_WDIR *dirp); + +static void seekdir(DIR *dirp, long loc); +static void _wseekdir(_WDIR *dirp, long loc); + +static int scandir(const char *dirname, struct dirent ***namelist, + int (*filter)(const struct dirent*), + int (*compare)(const struct dirent**, const struct dirent**)); + +static int alphasort(const struct dirent **a, const struct dirent **b); + +static int versionsort(const struct dirent **a, const struct dirent **b); + +static int strverscmp(const char *a, const char *b); + +/* For compatibility with Symbian */ +#define wdirent _wdirent +#define WDIR _WDIR +#define wopendir _wopendir +#define wreaddir _wreaddir +#define wclosedir _wclosedir +#define wrewinddir _wrewinddir +#define wtelldir _wtelldir +#define wseekdir _wseekdir + +/* Compatibility with older Microsoft compilers and non-Microsoft compilers */ +#if !defined(_MSC_VER) || _MSC_VER < 1400 +# define wcstombs_s dirent_wcstombs_s +# define mbstowcs_s dirent_mbstowcs_s +#endif + +/* Optimize dirent_set_errno() away on modern Microsoft compilers */ +#if defined(_MSC_VER) && _MSC_VER >= 1400 +# define dirent_set_errno _set_errno +#endif + + +/* Internal utility functions */ +static WIN32_FIND_DATAW *dirent_first(_WDIR *dirp); +static WIN32_FIND_DATAW *dirent_next(_WDIR *dirp); +static long dirent_hash(WIN32_FIND_DATAW *datap); + +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static int dirent_mbstowcs_s( + size_t *pReturnValue, wchar_t *wcstr, size_t sizeInWords, + const char *mbstr, size_t count); +#endif + +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static int dirent_wcstombs_s( + size_t *pReturnValue, char *mbstr, size_t sizeInBytes, + const wchar_t *wcstr, size_t count); +#endif + +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static void dirent_set_errno(int error); +#endif + + +/* + * Open directory stream DIRNAME for read and return a pointer to the + * internal working area that is used to retrieve individual directory + * entries. + */ +static _WDIR * +_wopendir(const wchar_t *dirname) +{ + wchar_t *p; + + /* Must have directory name */ + if (dirname == NULL || dirname[0] == '\0') { + dirent_set_errno(ENOENT); + return NULL; + } + + /* Allocate new _WDIR structure */ + _WDIR *dirp = (_WDIR*) malloc(sizeof(struct _WDIR)); + if (!dirp) + return NULL; + + /* Reset _WDIR structure */ + dirp->handle = INVALID_HANDLE_VALUE; + dirp->patt = NULL; + dirp->cached = 0; + dirp->invalid = 0; + + /* + * Compute the length of full path plus zero terminator + * + * Note that on WinRT there's no way to convert relative paths + * into absolute paths, so just assume it is an absolute path. + */ +#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) + /* Desktop */ + DWORD n = GetFullPathNameW(dirname, 0, NULL, NULL); +#else + /* WinRT */ + size_t n = wcslen(dirname); +#endif + + /* Allocate room for absolute directory name and search pattern */ + dirp->patt = (wchar_t*) malloc(sizeof(wchar_t) * n + 16); + if (dirp->patt == NULL) + goto exit_closedir; + + /* + * Convert relative directory name to an absolute one. This + * allows rewinddir() to function correctly even when current + * working directory is changed between opendir() and rewinddir(). + * + * Note that on WinRT there's no way to convert relative paths + * into absolute paths, so just assume it is an absolute path. + */ +#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) + /* Desktop */ + n = GetFullPathNameW(dirname, n, dirp->patt, NULL); + if (n <= 0) + goto exit_closedir; +#else + /* WinRT */ + wcsncpy_s(dirp->patt, n+1, dirname, n); +#endif + + /* Append search pattern \* to the directory name */ + p = dirp->patt + n; + switch (p[-1]) { + case '\\': + case '/': + case ':': + /* Directory ends in path separator, e.g. c:\temp\ */ + /*NOP*/; + break; + + default: + /* Directory name doesn't end in path separator */ + *p++ = '\\'; + } + *p++ = '*'; + *p = '\0'; + + /* Open directory stream and retrieve the first entry */ + if (!dirent_first(dirp)) + goto exit_closedir; + + /* Success */ + return dirp; + + /* Failure */ +exit_closedir: + _wclosedir(dirp); + return NULL; +} + +/* + * Read next directory entry. + * + * Returns pointer to static directory entry which may be overwritten by + * subsequent calls to _wreaddir(). + */ +static struct _wdirent * +_wreaddir(_WDIR *dirp) +{ + /* + * Read directory entry to buffer. We can safely ignore the return + * value as entry will be set to NULL in case of error. + */ + struct _wdirent *entry; + (void) _wreaddir_r(dirp, &dirp->ent, &entry); + + /* Return pointer to statically allocated directory entry */ + return entry; +} + +/* + * Read next directory entry. + * + * Returns zero on success. If end of directory stream is reached, then sets + * result to NULL and returns zero. + */ +static int +_wreaddir_r( + _WDIR *dirp, struct _wdirent *entry, struct _wdirent **result) +{ + /* Validate directory handle */ + if (!dirp || dirp->handle == INVALID_HANDLE_VALUE || !dirp->patt) { + dirent_set_errno(EBADF); + *result = NULL; + return -1; + } + + /* Read next directory entry */ + WIN32_FIND_DATAW *datap = dirent_next(dirp); + if (!datap) { + /* Return NULL to indicate end of directory */ + *result = NULL; + return /*OK*/0; + } + + /* + * Copy file name as wide-character string. If the file name is too + * long to fit in to the destination buffer, then truncate file name + * to PATH_MAX characters and zero-terminate the buffer. + */ + size_t i = 0; + while (i < PATH_MAX && datap->cFileName[i] != 0) { + entry->d_name[i] = datap->cFileName[i]; + i++; + } + entry->d_name[i] = 0; + + /* Length of file name excluding zero terminator */ + entry->d_namlen = i; + + /* Determine file type */ + DWORD attr = datap->dwFileAttributes; + if ((attr & FILE_ATTRIBUTE_DEVICE) != 0) + entry->d_type = DT_CHR; + else if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0) + entry->d_type = DT_DIR; + else + entry->d_type = DT_REG; + + /* Read the next directory entry to cache */ + datap = dirent_next(dirp); + if (datap) { + /* Compute 31-bit hash of the next directory entry */ + entry->d_off = dirent_hash(datap); + + /* Push the next directory entry back to cache */ + dirp->cached = 1; + } else { + /* End of directory stream */ + entry->d_off = (long) ((~0UL) >> 1); + } + + /* Reset other fields */ + entry->d_ino = 0; + entry->d_reclen = sizeof(struct _wdirent); + + /* Set result address */ + *result = entry; + return /*OK*/0; +} + +/* + * Close directory stream opened by opendir() function. This invalidates the + * DIR structure as well as any directory entry read previously by + * _wreaddir(). + */ +static int +_wclosedir(_WDIR *dirp) +{ + if (!dirp) { + dirent_set_errno(EBADF); + return /*failure*/-1; + } + + /* + * Release search handle if we have one. Being able to handle + * partially initialized _WDIR structure allows us to use this + * function to handle errors occuring within _wopendir. + */ + if (dirp->handle != INVALID_HANDLE_VALUE) { + FindClose(dirp->handle); + } + + /* + * Release search pattern. Note that we don't need to care if + * dirp->patt is NULL or not: function free is guaranteed to act + * appropriately. + */ + free(dirp->patt); + + /* Release directory structure */ + free(dirp); + return /*success*/0; +} + +/* + * Rewind directory stream such that _wreaddir() returns the very first + * file name again. + */ +static void _wrewinddir(_WDIR* dirp) +{ + /* Check directory pointer */ + if (!dirp || dirp->handle == INVALID_HANDLE_VALUE || !dirp->patt) + return; + + /* Release existing search handle */ + FindClose(dirp->handle); + + /* Open new search handle */ + dirent_first(dirp); +} + +/* Get first directory entry */ +static WIN32_FIND_DATAW * +dirent_first(_WDIR *dirp) +{ + /* Open directory and retrieve the first entry */ + dirp->handle = FindFirstFileExW( + dirp->patt, FindExInfoStandard, &dirp->data, + FindExSearchNameMatch, NULL, 0); + if (dirp->handle == INVALID_HANDLE_VALUE) + goto error; + + /* A directory entry is now waiting in memory */ + dirp->cached = 1; + return &dirp->data; + +error: + /* Failed to open directory: no directory entry in memory */ + dirp->cached = 0; + dirp->invalid = 1; + + /* Set error code */ + DWORD errorcode = GetLastError(); + switch (errorcode) { + case ERROR_ACCESS_DENIED: + /* No read access to directory */ + dirent_set_errno(EACCES); + break; + + case ERROR_DIRECTORY: + /* Directory name is invalid */ + dirent_set_errno(ENOTDIR); + break; + + case ERROR_PATH_NOT_FOUND: + default: + /* Cannot find the file */ + dirent_set_errno(ENOENT); + } + return NULL; +} + +/* Get next directory entry */ +static WIN32_FIND_DATAW * +dirent_next(_WDIR *dirp) +{ + /* Return NULL if seek position was invalid */ + if (dirp->invalid) + return NULL; + + /* Is the next directory entry already in cache? */ + if (dirp->cached) { + /* Yes, a valid directory entry found in memory */ + dirp->cached = 0; + return &dirp->data; + } + + /* Read the next directory entry from stream */ + if (FindNextFileW(dirp->handle, &dirp->data) == FALSE) { + /* End of directory stream */ + return NULL; + } + + /* Success */ + return &dirp->data; +} + +/* + * Compute 31-bit hash of file name. + * + * See djb2 at http://www.cse.yorku.ca/~oz/hash.html + */ +static long +dirent_hash(WIN32_FIND_DATAW *datap) +{ + unsigned long hash = 5381; + unsigned long c; + const wchar_t *p = datap->cFileName; + const wchar_t *e = p + MAX_PATH; + while (p != e && (c = *p++) != 0) { + hash = (hash << 5) + hash + c; + } + + return (long) (hash & ((~0UL) >> 1)); +} + +/* Open directory stream using plain old C-string */ +static DIR *opendir(const char *dirname) +{ + /* Must have directory name */ + if (dirname == NULL || dirname[0] == '\0') { + dirent_set_errno(ENOENT); + return NULL; + } + + /* Allocate memory for DIR structure */ + struct DIR *dirp = (DIR*) malloc(sizeof(struct DIR)); + if (!dirp) + return NULL; + + /* Convert directory name to wide-character string */ + wchar_t wname[PATH_MAX + 1]; + size_t n; + int error = mbstowcs_s(&n, wname, PATH_MAX + 1, dirname, PATH_MAX+1); + if (error) + goto exit_failure; + + /* Open directory stream using wide-character name */ + dirp->wdirp = _wopendir(wname); + if (!dirp->wdirp) + goto exit_failure; + + /* Success */ + return dirp; + + /* Failure */ +exit_failure: + free(dirp); + return NULL; +} + +/* Read next directory entry */ +static struct dirent * +readdir(DIR *dirp) +{ + /* + * Read directory entry to buffer. We can safely ignore the return + * value as entry will be set to NULL in case of error. + */ + struct dirent *entry; + (void) readdir_r(dirp, &dirp->ent, &entry); + + /* Return pointer to statically allocated directory entry */ + return entry; +} + +/* + * Read next directory entry into called-allocated buffer. + * + * Returns zero on success. If the end of directory stream is reached, then + * sets result to NULL and returns zero. + */ +static int +readdir_r( + DIR *dirp, struct dirent *entry, struct dirent **result) +{ + /* Read next directory entry */ + WIN32_FIND_DATAW *datap = dirent_next(dirp->wdirp); + if (!datap) { + /* No more directory entries */ + *result = NULL; + return /*OK*/0; + } + + /* Attempt to convert file name to multi-byte string */ + size_t n; + int error = wcstombs_s( + &n, entry->d_name, PATH_MAX + 1, + datap->cFileName, PATH_MAX + 1); + + /* + * If the file name cannot be represented by a multi-byte string, then + * attempt to use old 8+3 file name. This allows the program to + * access files although file names may seem unfamiliar to the user. + * + * Be ware that the code below cannot come up with a short file name + * unless the file system provides one. At least VirtualBox shared + * folders fail to do this. + */ + if (error && datap->cAlternateFileName[0] != '\0') { + error = wcstombs_s( + &n, entry->d_name, PATH_MAX + 1, + datap->cAlternateFileName, PATH_MAX + 1); + } + + if (!error) { + /* Length of file name excluding zero terminator */ + entry->d_namlen = n - 1; + + /* Determine file type */ + DWORD attr = datap->dwFileAttributes; + if ((attr & FILE_ATTRIBUTE_DEVICE) != 0) + entry->d_type = DT_CHR; + else if ((attr & FILE_ATTRIBUTE_DIRECTORY) != 0) + entry->d_type = DT_DIR; + else + entry->d_type = DT_REG; + + /* Get offset of next file */ + datap = dirent_next(dirp->wdirp); + if (datap) { + /* Compute 31-bit hash of the next directory entry */ + entry->d_off = dirent_hash(datap); + + /* Push the next directory entry back to cache */ + dirp->wdirp->cached = 1; + } else { + /* End of directory stream */ + entry->d_off = (long) ((~0UL) >> 1); + } + + /* Reset fields */ + entry->d_ino = 0; + entry->d_reclen = sizeof(struct dirent); + } else { + /* + * Cannot convert file name to multi-byte string so construct + * an erroneous directory entry and return that. Note that + * we cannot return NULL as that would stop the processing + * of directory entries completely. + */ + entry->d_name[0] = '?'; + entry->d_name[1] = '\0'; + entry->d_namlen = 1; + entry->d_type = DT_UNKNOWN; + entry->d_ino = 0; + entry->d_off = -1; + entry->d_reclen = 0; + } + + /* Return pointer to directory entry */ + *result = entry; + return /*OK*/0; +} + +/* Close directory stream */ +static int +closedir(DIR *dirp) +{ + int ok; + + if (!dirp) + goto exit_failure; + + /* Close wide-character directory stream */ + ok = _wclosedir(dirp->wdirp); + dirp->wdirp = NULL; + + /* Release multi-byte character version */ + free(dirp); + return ok; + +exit_failure: + /* Invalid directory stream */ + dirent_set_errno(EBADF); + return /*failure*/-1; +} + +/* Rewind directory stream to beginning */ +static void +rewinddir(DIR *dirp) +{ + if (!dirp) + return; + + /* Rewind wide-character string directory stream */ + _wrewinddir(dirp->wdirp); +} + +/* Get position of directory stream */ +static long +_wtelldir(_WDIR *dirp) +{ + if (!dirp || dirp->handle == INVALID_HANDLE_VALUE) { + dirent_set_errno(EBADF); + return /*failure*/-1; + } + + /* Read next file entry */ + WIN32_FIND_DATAW *datap = dirent_next(dirp); + if (!datap) { + /* End of directory stream */ + return (long) ((~0UL) >> 1); + } + + /* Store file entry to cache for readdir() */ + dirp->cached = 1; + + /* Return the 31-bit hash code to be used as stream position */ + return dirent_hash(datap); +} + +/* Get position of directory stream */ +static long +telldir(DIR *dirp) +{ + if (!dirp) { + dirent_set_errno(EBADF); + return -1; + } + + return _wtelldir(dirp->wdirp); +} + +/* Seek directory stream to offset */ +static void +_wseekdir(_WDIR *dirp, long loc) +{ + /* Directory must be open */ + if (!dirp || dirp->handle == INVALID_HANDLE_VALUE) + goto exit_failure; + + /* Ensure that seek position is valid */ + if (loc < 0) + goto exit_failure; + + /* Restart directory stream from the beginning */ + FindClose(dirp->handle); + if (!dirent_first(dirp)) + goto exit_failure; + + /* Reset invalid flag so that we can read from the stream again */ + dirp->invalid = 0; + + /* + * Read directory entries from the beginning until the hash matches a + * file name. Be ware that hash code is only 31 bits longs and + * duplicates are possible: the hash code cannot return the position + * with 100.00% accuracy! Moreover, the method is slow for large + * directories. + */ + long hash; + do { + /* Read next directory entry */ + WIN32_FIND_DATAW *datap = dirent_next(dirp); + if (!datap) { + /* + * End of directory stream was reached before finding + * the requested location. Perhaps the file in + * question was deleted or moved out of the directory. + */ + goto exit_failure; + } + + /* Does the file name match the hash? */ + hash = dirent_hash(datap); + } while (hash != loc); + + /* + * File name matches the hash! Push the directory entry back to cache + * from where next readdir() will return it. + */ + dirp->cached = 1; + dirp->invalid = 0; + return; + +exit_failure: + /* Ensure that readdir will return NULL */ + dirp->invalid = 1; +} + +/* Seek directory stream to offset */ +static void +seekdir(DIR *dirp, long loc) +{ + if (!dirp) + return; + + _wseekdir(dirp->wdirp, loc); +} + +/* Scan directory for entries */ +static int +scandir( + const char *dirname, struct dirent ***namelist, + int (*filter)(const struct dirent*), + int (*compare)(const struct dirent**, const struct dirent**)) +{ + int result; + + /* Open directory stream */ + DIR *dir = opendir(dirname); + if (!dir) { + /* Cannot open directory */ + return /*Error*/ -1; + } + + /* Read directory entries to memory */ + struct dirent *tmp = NULL; + struct dirent **files = NULL; + size_t size = 0; + size_t allocated = 0; + while (1) { + /* Allocate room for a temporary directory entry */ + if (!tmp) { + tmp = (struct dirent*) malloc(sizeof(struct dirent)); + if (!tmp) + goto exit_failure; + } + + /* Read directory entry to temporary area */ + struct dirent *entry; + if (readdir_r(dir, tmp, &entry) != /*OK*/0) + goto exit_failure; + + /* Stop if we already read the last directory entry */ + if (entry == NULL) + goto exit_success; + + /* Determine whether to include the entry in results */ + if (filter && !filter(tmp)) + continue; + + /* Enlarge pointer table to make room for another pointer */ + if (size >= allocated) { + /* Compute number of entries in the new table */ + size_t num_entries = size * 2 + 16; + + /* Allocate new pointer table or enlarge existing */ + void *p = realloc(files, sizeof(void*) * num_entries); + if (!p) + goto exit_failure; + + /* Got the memory */ + files = (dirent**) p; + allocated = num_entries; + } + + /* Store the temporary entry to ptr table */ + files[size++] = tmp; + tmp = NULL; + } + +exit_failure: + /* Release allocated entries */ + for (size_t i = 0; i < size; i++) { + free(files[i]); + } + + /* Release the pointer table */ + free(files); + files = NULL; + + /* Exit with error code */ + result = /*error*/ -1; + goto exit_status; + +exit_success: + /* Sort directory entries */ + qsort(files, size, sizeof(void*), + (int (*) (const void*, const void*)) compare); + + /* Pass pointer table to caller */ + if (namelist) + *namelist = files; + + /* Return the number of directory entries read */ + result = (int) size; + +exit_status: + /* Release temporary directory entry, if we had one */ + free(tmp); + + /* Close directory stream */ + closedir(dir); + return result; +} + +/* Alphabetical sorting */ +static int +alphasort(const struct dirent **a, const struct dirent **b) +{ + return strcoll((*a)->d_name, (*b)->d_name); +} + +/* Sort versions */ +static int +versionsort(const struct dirent **a, const struct dirent **b) +{ + return strverscmp((*a)->d_name, (*b)->d_name); +} + +/* Compare strings */ +static int +strverscmp(const char *a, const char *b) +{ + size_t i = 0; + size_t j; + + /* Find first difference */ + while (a[i] == b[i]) { + if (a[i] == '\0') { + /* No difference */ + return 0; + } + ++i; + } + + /* Count backwards and find the leftmost digit */ + j = i; + while (j > 0 && isdigit(a[j-1])) { + --j; + } + + /* Determine mode of comparison */ + if (a[j] == '0' || b[j] == '0') { + /* Find the next non-zero digit */ + while (a[j] == '0' && a[j] == b[j]) { + j++; + } + + /* String with more digits is smaller, e.g 002 < 01 */ + if (isdigit(a[j])) { + if (!isdigit(b[j])) { + return -1; + } + } else if (isdigit(b[j])) { + return 1; + } + } else if (isdigit(a[j]) && isdigit(b[j])) { + /* Numeric comparison */ + size_t k1 = j; + size_t k2 = j; + + /* Compute number of digits in each string */ + while (isdigit(a[k1])) { + k1++; + } + while (isdigit(b[k2])) { + k2++; + } + + /* Number with more digits is bigger, e.g 999 < 1000 */ + if (k1 < k2) + return -1; + else if (k1 > k2) + return 1; + } + + /* Alphabetical comparison */ + return (int) ((unsigned char) a[i]) - ((unsigned char) b[i]); +} + +/* Convert multi-byte string to wide character string */ +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static int +dirent_mbstowcs_s( + size_t *pReturnValue, wchar_t *wcstr, + size_t sizeInWords, const char *mbstr, size_t count) +{ + /* Older Visual Studio or non-Microsoft compiler */ + size_t n = mbstowcs(wcstr, mbstr, sizeInWords); + if (wcstr && n >= count) + return /*error*/ 1; + + /* Zero-terminate output buffer */ + if (wcstr && sizeInWords) { + if (n >= sizeInWords) + n = sizeInWords - 1; + wcstr[n] = 0; + } + + /* Length of multi-byte string with zero terminator */ + if (pReturnValue) { + *pReturnValue = n + 1; + } + + /* Success */ + return 0; +} +#endif + +/* Convert wide-character string to multi-byte string */ +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static int +dirent_wcstombs_s( + size_t *pReturnValue, char *mbstr, + size_t sizeInBytes, const wchar_t *wcstr, size_t count) +{ + /* Older Visual Studio or non-Microsoft compiler */ + size_t n = wcstombs(mbstr, wcstr, sizeInBytes); + if (mbstr && n >= count) + return /*error*/1; + + /* Zero-terminate output buffer */ + if (mbstr && sizeInBytes) { + if (n >= sizeInBytes) { + n = sizeInBytes - 1; + } + mbstr[n] = '\0'; + } + + /* Length of resulting multi-bytes string WITH zero-terminator */ + if (pReturnValue) { + *pReturnValue = n + 1; + } + + /* Success */ + return 0; +} +#endif + +/* Set errno variable */ +#if !defined(_MSC_VER) || _MSC_VER < 1400 +static void +dirent_set_errno(int error) +{ + /* Non-Microsoft compiler or older Microsoft compiler */ + errno = error; +} +#endif + +#ifdef __cplusplus +} +#endif +#endif /*DIRENT_H*/ |