/*

 * Posix-esque support routines for PhysicsFS.

 *

 * Please see the file LICENSE in the source's root directory.

 *

 *  This file written by Ryan C. Gordon.

 */

#if HAVE_CONFIG_H

#  include <config.h>

#endif

#if (!defined WIN32)

#if (defined __STRICT_ANSI__)

#define __PHYSFS_DOING_STRICT_ANSI__

#endif

/*

 * We cheat a little: I want the symlink version of stat() (lstat), and

 *  GCC/Linux will not declare it if compiled with the -ansi flag.

 *  If you are really lacking symlink support on your platform,

 *  you should #define __PHYSFS_NO_SYMLINKS__ before compiling this

 *  file. That will open a security hole, though, if you really DO have

 *  symlinks on your platform; it renders PHYSFS_permitSymbolicLinks(0)

 *  useless, since every symlink will be reported as a regular file/dir.

 */

#if (defined __PHYSFS_DOING_STRICT_ANSI__)

#undef __STRICT_ANSI__

#endif

#include <stdio.h>

#if (defined __PHYSFS_DOING_STRICT_ANSI__)

#define __STRICT_ANSI__

#endif

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <ctype.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <pwd.h>

#include <dirent.h>

#include <errno.h>

#include <fcntl.h>

#ifdef PHYSFS_HAVE_LLSEEK

#include <linux/unistd.h>

#endif

#define __PHYSICSFS_INTERNAL__

#include "physfs_internal.h"

char *__PHYSFS_platformCopyEnvironmentVariable(const char *varname)

{

    const char *envr = getenv(varname);

    char *retval = NULL;

    if (envr != NULL)

    {

        retval = (char *) malloc(strlen(envr) + 1);

        if (retval != NULL)

            strcpy(retval, envr);

    } /* if */

    return(retval);

} /* __PHYSFS_platformCopyEnvironmentVariable */

static char *getUserNameByUID(void)

{

    uid_t uid = getuid();

    struct passwd *pw;

    char *retval = NULL;

    pw = getpwuid(uid);

    if ((pw != NULL) && (pw->pw_name != NULL))

    {

        retval = (char *) malloc(strlen(pw->pw_name) + 1);

        if (retval != NULL)

            strcpy(retval, pw->pw_name);

    } /* if */

    return(retval);

} /* getUserNameByUID */

static char *getUserDirByUID(void)

{

    uid_t uid = getuid();

    struct passwd *pw;

    char *retval = NULL;

    pw = getpwuid(uid);

    if ((pw != NULL) && (pw->pw_dir != NULL))

    {

        retval = (char *) malloc(strlen(pw->pw_dir) + 1);

        if (retval != NULL)

            strcpy(retval, pw->pw_dir);

    } /* if */

    return(retval);

} /* getUserDirByUID */

char *__PHYSFS_platformGetUserName(void)

{

    char *retval = getUserNameByUID();

    if (retval == NULL)

        retval = __PHYSFS_platformCopyEnvironmentVariable("USER");

    return(retval);

} /* __PHYSFS_platformGetUserName */

char *__PHYSFS_platformGetUserDir(void)

{

    char *retval = __PHYSFS_platformCopyEnvironmentVariable("HOME");

    if (retval == NULL)

        retval = getUserDirByUID();

    return(retval);

} /* __PHYSFS_platformGetUserDir */

/* -ansi and -pedantic flags prevent use of strcasecmp() on Linux. */

int __PHYSFS_platformStricmp(const char *x, const char *y)

{

    int ux, uy;

    do

    {

        ux = toupper((int) *x);

        uy = toupper((int) *y);

        if (ux > uy)

            return(1);

        else if (ux < uy)

            return(-1);

        x++;

        y++;

    } while ((ux) && (uy));

    return(0);

} /* __PHYSFS_platformStricmp */

#if (defined __PHYSFS_NO_SYMLINKS__)

#define doStat stat

#else

#define doStat lstat

#endif

int __PHYSFS_platformExists(const char *fname)

{

    struct stat statbuf;

    BAIL_IF_MACRO(doStat(fname, &statbuf) == -1, strerror(errno), 0);

    return(1);

} /* __PHYSFS_platformExists */

int __PHYSFS_platformIsSymLink(const char *fname)

{

#if (defined __PHYSFS_NO_SYMLINKS__)

    return(0);

#else

    struct stat statbuf;

    BAIL_IF_MACRO(lstat(fname, &statbuf) == -1, strerror(errno), 0);

    return( (S_ISLNK(statbuf.st_mode)) ? 1 : 0 );

#endif

} /* __PHYSFS_platformIsSymlink */

int __PHYSFS_platformIsDirectory(const char *fname)

{

    struct stat statbuf;

    BAIL_IF_MACRO(stat(fname, &statbuf) == -1, strerror(errno), 0);

    return( (S_ISDIR(statbuf.st_mode)) ? 1 : 0 );

} /* __PHYSFS_platformIsDirectory */

char *__PHYSFS_platformCvtToDependent(const char *prepend,

                                      const char *dirName,

                                      const char *append)

{

    int len = ((prepend) ? strlen(prepend) : 0) +

              ((append) ? strlen(append) : 0) +

              strlen(dirName) + 1;

    char *retval = (char *) malloc(len);

    BAIL_IF_MACRO(retval == NULL, ERR_OUT_OF_MEMORY, NULL);

    /* platform-independent notation is Unix-style already.  :)  */

    if (prepend)

        strcpy(retval, prepend);

    else

        retval[0] = '\0';

    strcat(retval, dirName);

    if (append)

        strcat(retval, append);

    return(retval);

} /* __PHYSFS_platformCvtToDependent */

LinkedStringList *__PHYSFS_platformEnumerateFiles(const char *dirname,

                                                  int omitSymLinks)

{

    LinkedStringList *retval = NULL, *p = NULL;

    DIR *dir;

    struct dirent *ent;

    int bufsize = 0;

    char *buf = NULL;

    int dlen = 0;

    if (omitSymLinks)

    {

        dlen = strlen(dirname);

        bufsize = dlen + 256;

        buf = (char *) malloc(bufsize);

        BAIL_IF_MACRO(buf == NULL, ERR_OUT_OF_MEMORY, NULL);

        strcpy(buf, dirname);

        if (buf[dlen - 1] != '/')

        {

            buf[dlen++] = '/';

            buf[dlen] = '\0';

        } /* if */

    } /* if */

    errno = 0;

    dir = opendir(dirname);

    if (dir == NULL)

    {

        if (buf != NULL)

            free(buf);

        BAIL_IF_MACRO(1, strerror(errno), NULL);

    } /* if */

    while ((ent = readdir(dir)) != NULL)

    {

        if (strcmp(ent->d_name, ".") == 0)

            continue;

        if (strcmp(ent->d_name, "..") == 0)

            continue;

        if (omitSymLinks)

        {

            char *p;

            int len = strlen(ent->d_name) + dlen + 1;

            if (len > bufsize)

            {

                p = realloc(buf, len);

                if (p == NULL)

                    continue;

                buf = p;

                bufsize = len;

            } /* if */

            strcpy(buf + dlen, ent->d_name);

            if (__PHYSFS_platformIsSymLink(buf))

                continue;

        } /* if */

        retval = __PHYSFS_addToLinkedStringList(retval, &p, ent->d_name, -1);

    } /* while */

    if (buf != NULL)

        free(buf);

    closedir(dir);

    return(retval);

} /* __PHYSFS_platformEnumerateFiles */

char *__PHYSFS_platformCurrentDir(void)

{

    int allocSize = 0;

    char *retval = NULL;

    char *ptr;

    do

    {

        allocSize += 100;

        ptr = (char *) realloc(retval, allocSize);

        if (ptr == NULL)

        {

            if (retval != NULL)

                free(retval);

            BAIL_MACRO(ERR_OUT_OF_MEMORY, NULL);

        } /* if */

        retval = ptr;

        ptr = getcwd(retval, allocSize);

    } while (ptr == NULL && errno == ERANGE);

    if (ptr == NULL && errno)

    {

            /*

             * getcwd() failed for some reason, for example current

             * directory not existing.

             */

        if (retval != NULL)

            free(retval);

        BAIL_MACRO(ERR_NO_SUCH_FILE, NULL);

    } /* if */

    return(retval);

} /* __PHYSFS_platformCurrentDir */

int __PHYSFS_platformMkDir(const char *path)

{

    int rc;

    errno = 0;

    rc = mkdir(path, S_IRWXU);

    BAIL_IF_MACRO(rc == -1, strerror(errno), 0);

    return(1);

} /* __PHYSFS_platformMkDir */

static void *doOpen(const char *filename, int mode)

{

    int fd;

    int *retval;

    errno = 0;

    fd = open(filename, mode, S_IRUSR | S_IWUSR);

    BAIL_IF_MACRO(fd < 0, strerror(errno), NULL);

    retval = (int *) malloc(sizeof (int));

    if (retval == NULL)

    {

        close(fd);

        BAIL_MACRO(ERR_OUT_OF_MEMORY, NULL);

    } /* if */

    *retval = fd;

    return((void *) retval);

} /* doOpen */

void *__PHYSFS_platformOpenRead(const char *filename)

{

    return(doOpen(filename, O_RDONLY));

} /* __PHYSFS_platformOpenRead */

void *__PHYSFS_platformOpenWrite(const char *filename)

{

    return(doOpen(filename, O_WRONLY | O_CREAT | O_TRUNC));

} /* __PHYSFS_platformOpenWrite */

void *__PHYSFS_platformOpenAppend(const char *filename)

{

    return(doOpen(filename, O_WRONLY | O_CREAT | O_APPEND));

} /* __PHYSFS_platformOpenAppend */

PHYSFS_sint64 __PHYSFS_platformRead(void *opaque, void *buffer,

                                    PHYSFS_uint32 size, PHYSFS_uint32 count)

{

    int fd = *((int *) opaque);

    int max = size * count;

    int rc = read(fd, buffer, max);

    BAIL_IF_MACRO(rc == -1, strerror(errno), rc);

    assert(rc <= max);

    if ((rc < max) && (size > 1))

        lseek(fd, -(rc % size), SEEK_CUR); /* rollback to object boundary. */

    return(rc / size);

} /* __PHYSFS_platformRead */

PHYSFS_sint64 __PHYSFS_platformWrite(void *opaque, const void *buffer,

                                     PHYSFS_uint32 size, PHYSFS_uint32 count)

{

    int fd = *((int *) opaque);

    int max = size * count;

    int rc = write(fd, (void *) buffer, max);

    BAIL_IF_MACRO(rc == -1, strerror(errno), rc);

    assert(rc <= max);

    if ((rc < max) && (size > 1))

        lseek(fd, -(rc % size), SEEK_CUR); /* rollback to object boundary. */

    return(rc / size);

} /* __PHYSFS_platformWrite */

int __PHYSFS_platformSeek(void *opaque, PHYSFS_uint64 pos)

{

    int fd = *((int *) opaque);

    #ifdef PHYSFS_HAVE_LLSEEK

      unsigned long offset_high = ((pos >> 32) & 0xFFFFFFFF);

      unsigned long offset_low = (pos & 0xFFFFFFFF);

      loff_t retoffset;

      int rc = llseek(fd, offset_high, offset_low, &retoffset, SEEK_SET);

      BAIL_IF_MACRO(rc == -1, strerror(errno), 0);

    #else

      BAIL_IF_MACRO(lseek(fd, (int) pos, SEEK_SET) == -1, strerror(errno), 0);

    #endif

    return(1);

} /* __PHYSFS_platformSeek */

PHYSFS_sint64 __PHYSFS_platformTell(void *opaque)

{

    int fd = *((int *) opaque);

    PHYSFS_sint64 retval;

    #ifdef PHYSFS_HAVE_LLSEEK

      loff_t retoffset;

      int rc = llseek(fd, 0, &retoffset, SEEK_CUR);

      BAIL_IF_MACRO(rc == -1, strerror(errno), -1);

      retval = (PHYSFS_sint64) retoffset;

    #else

      retval = (PHYSFS_sint64) lseek(fd, 0, SEEK_CUR);

      BAIL_IF_MACRO(retval == -1, strerror(errno), -1);

    #endif

    return(retval);

} /* __PHYSFS_platformTell */

PHYSFS_sint64 __PHYSFS_platformFileLength(void *opaque)

{

    int fd = *((int *) opaque);

    struct stat statbuf;

    BAIL_IF_MACRO(fstat(fd, &statbuf) == -1, strerror(errno), -1);

    return((PHYSFS_sint64) statbuf.st_size);

} /* __PHYSFS_platformFileLength */

int __PHYSFS_platformEOF(void *opaque)

{

    PHYSFS_sint64 pos = __PHYSFS_platformTell(opaque);

    PHYSFS_sint64 len = __PHYSFS_platformFileLength(opaque);

    return(pos >= len);

} /* __PHYSFS_platformEOF */

int __PHYSFS_platformFlush(void *opaque)

{

    int fd = *((int *) opaque);

    BAIL_IF_MACRO(fsync(fd) == -1, strerror(errno), 0);

    return(1);

} /* __PHYSFS_platformFlush */

int __PHYSFS_platformClose(void *opaque)

{

    int fd = *((int *) opaque);

    BAIL_IF_MACRO(close(fd) == -1, strerror(errno), 0);

    free(opaque);

    return(1);

} /* __PHYSFS_platformClose */

int __PHYSFS_platformDelete(const char *path)

{

    BAIL_IF_MACRO(remove(path) == -1, strerror(errno), 0);

    return(1);

} /* __PHYSFS_platformDelete */

PHYSFS_sint64 __PHYSFS_platformGetLastModTime(const char *fname)

{

    struct stat statbuf;

    BAIL_IF_MACRO(stat(fname, &statbuf) < 0, strerror(errno), -1);

    return statbuf.st_mtime;

} /* __PHYSFS_platformGetLastModTime */

#endif /* !defined WIN32 */

/* end of posix.c ... */