physfs/platform/unix.c

447 lines
11 KiB
C

/*
* Unix support routines for PhysicsFS.
*
* Please see the file LICENSE.txt in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
#define __PHYSICSFS_INTERNAL__
#include "physfs_platforms.h"
#ifdef PHYSFS_PLATFORM_UNIX
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>
#include <sys/stat.h>
#include <sys/param.h>
#include <dirent.h>
#include <time.h>
#include <errno.h>
#if (!defined PHYSFS_NO_THREAD_SUPPORT)
#include <pthread.h>
#endif
#ifdef PHYSFS_HAVE_SYS_UCRED_H
# ifdef PHYSFS_HAVE_MNTENT_H
# undef PHYSFS_HAVE_MNTENT_H /* don't do both... */
# endif
# include <sys/ucred.h>
# include <sys/mount.h>
#endif
#ifdef PHYSFS_HAVE_MNTENT_H
#include <mntent.h>
#endif
#include "physfs_internal.h"
#ifndef MAXPATHLEN
#define MAXPATHLEN 1024
#endif
int __PHYSFS_platformInit(void)
{
return(1); /* always succeed. */
} /* __PHYSFS_platformInit */
int __PHYSFS_platformDeinit(void)
{
return(1); /* always succeed. */
} /* __PHYSFS_platformDeinit */
#ifdef PHYSFS_NO_CDROM_SUPPORT
/* Stub version for platforms without CD-ROM support. */
void __PHYSFS_platformDetectAvailableCDs(PHYSFS_StringCallback cb, void *data)
{
} /* __PHYSFS_platformDetectAvailableCDs */
#elif (defined PHYSFS_HAVE_SYS_UCRED_H)
void __PHYSFS_platformDetectAvailableCDs(PHYSFS_StringCallback cb, void *data)
{
int i;
struct statfs *mntbufp = NULL;
int mounts = getmntinfo(&mntbufp, MNT_WAIT);
for (i = 0; i < mounts; i++)
{
int add_it = 0;
if (strcmp(mntbufp[i].f_fstypename, "iso9660") == 0)
add_it = 1;
else if (strcmp( mntbufp[i].f_fstypename, "cd9660") == 0)
add_it = 1;
/* add other mount types here */
if (add_it)
cb(data, mntbufp[i].f_mntonname);
} /* for */
} /* __PHYSFS_platformDetectAvailableCDs */
#elif (defined PHYSFS_HAVE_MNTENT_H)
void __PHYSFS_platformDetectAvailableCDs(PHYSFS_StringCallback cb, void *data)
{
FILE *mounts = NULL;
struct mntent *ent = NULL;
mounts = setmntent("/etc/mtab", "r");
BAIL_IF_MACRO(mounts == NULL, ERR_IO_ERROR, /*return void*/);
while ( (ent = getmntent(mounts)) != NULL )
{
int add_it = 0;
if (strcmp(ent->mnt_type, "iso9660") == 0)
add_it = 1;
else if (strcmp(ent->mnt_type, "udf") == 0)
add_it = 1;
/* !!! FIXME: these might pick up floppy drives, right? */
else if (strcmp(ent->mnt_type, "auto") == 0)
add_it = 1;
else if (strcmp(ent->mnt_type, "supermount") == 0)
add_it = 1;
/* add other mount types here */
if (add_it)
cb(data, ent->mnt_dir);
} /* while */
endmntent(mounts);
} /* __PHYSFS_platformDetectAvailableCDs */
#endif
/* this is in posix.c ... */
extern char *__PHYSFS_platformCopyEnvironmentVariable(const char *varname);
/*
* See where program (bin) resides in the $PATH specified by (envr).
* returns a copy of the first element in envr that contains it, or NULL
* if it doesn't exist or there were other problems. PHYSFS_SetError() is
* called if we have a problem.
*
* (envr) will be scribbled over, and you are expected to allocator.Free() the
* return value when you're done with it.
*/
static char *findBinaryInPath(const char *bin, char *envr)
{
size_t alloc_size = 0;
char *exe = NULL;
char *start = envr;
char *ptr;
BAIL_IF_MACRO(bin == NULL, ERR_INVALID_ARGUMENT, NULL);
BAIL_IF_MACRO(envr == NULL, ERR_INVALID_ARGUMENT, NULL);
do
{
size_t size;
ptr = strchr(start, ':'); /* find next $PATH separator. */
if (ptr)
*ptr = '\0';
size = strlen(start) + strlen(bin) + 2;
if (size > alloc_size)
{
char *x = (char *) allocator.Realloc(exe, size);
if (x == NULL)
{
if (exe != NULL)
allocator.Free(exe);
BAIL_MACRO(ERR_OUT_OF_MEMORY, NULL);
} /* if */
alloc_size = size;
exe = x;
} /* if */
/* build full binary path... */
strcpy(exe, start);
if ((exe[0] == '\0') || (exe[strlen(exe) - 1] != '/'))
strcat(exe, "/");
strcat(exe, bin);
if (access(exe, X_OK) == 0) /* Exists as executable? We're done. */
{
strcpy(exe, start); /* i'm lazy. piss off. */
return(exe);
} /* if */
start = ptr + 1; /* start points to beginning of next element. */
} while (ptr != NULL);
if (exe != NULL)
allocator.Free(exe);
return(NULL); /* doesn't exist in path. */
} /* findBinaryInPath */
static char *readSymLink(const char *path)
{
ssize_t len = 64;
ssize_t rc = -1;
char *retval = NULL;
while (1)
{
char *ptr = (char *) allocator.Realloc(retval, (size_t) len);
if (ptr == NULL)
break; /* out of memory. */
retval = ptr;
rc = readlink(path, retval, len);
if (rc == -1)
break; /* not a symlink, i/o error, etc. */
else if (rc < len)
{
retval[rc] = '\0'; /* readlink doesn't null-terminate. */
return retval; /* we're good to go. */
} /* else if */
len *= 2; /* grow buffer, try again. */
} /* while */
if (retval != NULL)
allocator.Free(retval);
return NULL;
} /* readSymLink */
char *__PHYSFS_platformCalcBaseDir(const char *argv0)
{
char *retval = NULL;
char *envr = NULL;
/* fast path: default behaviour can handle this. */
if ( (argv0 != NULL) && (strchr(argv0, '/') != NULL) )
return(NULL); /* higher level will parse out real path from argv0. */
/*
* Try to avoid using argv0 unless forced to. If there's a Linux-like
* /proc filesystem, you can get the full path to the current process from
* the /proc/self/exe symlink.
*/
retval = readSymLink("/proc/self/exe");
if (retval == NULL)
{
/* older kernels don't have /proc/self ... try PID version... */
const unsigned long long pid = (unsigned long long) getpid();
char path[64];
const int rc = (int) snprintf(path,sizeof(path),"/proc/%llu/exe",pid);
if ( (rc > 0) && (rc < sizeof(path)) )
retval = readSymLink(path);
} /* if */
if (retval != NULL) /* chop off filename. */
{
char *ptr = strrchr(retval, '/');
if (ptr != NULL)
*ptr = '\0';
} /* if */
if ((retval == NULL) && (argv0 != NULL))
{
/* If there's no dirsep on argv0, then look through $PATH for it. */
envr = __PHYSFS_platformCopyEnvironmentVariable("PATH");
BAIL_IF_MACRO(!envr, NULL, NULL);
retval = findBinaryInPath(argv0, envr);
allocator.Free(envr);
} /* if */
if (retval != NULL)
{
/* try to shrink buffer... */
char *ptr = (char *) allocator.Realloc(retval, strlen(retval) + 1);
if (ptr != NULL)
retval = ptr; /* oh well if it failed. */
} /* if */
return(retval);
} /* __PHYSFS_platformCalcBaseDir */
char *__PHYSFS_platformRealPath(const char *path)
{
char resolved_path[MAXPATHLEN];
char *retval = NULL;
errno = 0;
BAIL_IF_MACRO(!realpath(path, resolved_path), strerror(errno), NULL);
retval = (char *) allocator.Malloc(strlen(resolved_path) + 1);
BAIL_IF_MACRO(retval == NULL, ERR_OUT_OF_MEMORY, NULL);
strcpy(retval, resolved_path);
return(retval);
} /* __PHYSFS_platformRealPath */
char *__PHYSFS_platformCurrentDir(void)
{
/*
* This can't just do platformRealPath("."), since that would eventually
* just end up calling back into here.
*/
int allocSize = 0;
char *retval = NULL;
char *ptr;
do
{
allocSize += 100;
ptr = (char *) allocator.Realloc(retval, allocSize);
if (ptr == NULL)
{
if (retval != NULL)
allocator.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)
allocator.Free(retval);
BAIL_MACRO(ERR_NO_SUCH_FILE, NULL);
} /* if */
return(retval);
} /* __PHYSFS_platformCurrentDir */
int __PHYSFS_platformSetDefaultAllocator(PHYSFS_Allocator *a)
{
return(0); /* just use malloc() and friends. */
} /* __PHYSFS_platformSetDefaultAllocator */
#if (defined PHYSFS_NO_THREAD_SUPPORT)
PHYSFS_uint64 __PHYSFS_platformGetThreadID(void) { return(0x0001); }
void *__PHYSFS_platformCreateMutex(void) { return((void *) 0x0001); }
void __PHYSFS_platformDestroyMutex(void *mutex) {}
int __PHYSFS_platformGrabMutex(void *mutex) { return(1); }
void __PHYSFS_platformReleaseMutex(void *mutex) {}
#else
typedef struct
{
pthread_mutex_t mutex;
pthread_t owner;
PHYSFS_uint32 count;
} PthreadMutex;
/* Just in case; this is a panic value. */
#if ((!defined SIZEOF_INT) || (SIZEOF_INT <= 0))
# define SIZEOF_INT 4
#endif
#if (SIZEOF_INT == 4)
# define PHTREAD_TO_UI64(thr) ( (PHYSFS_uint64) ((PHYSFS_uint32) (thr)) )
#elif (SIZEOF_INT == 2)
# define PHTREAD_TO_UI64(thr) ( (PHYSFS_uint64) ((PHYSFS_uint16) (thr)) )
#elif (SIZEOF_INT == 1)
# define PHTREAD_TO_UI64(thr) ( (PHYSFS_uint64) ((PHYSFS_uint8) (thr)) )
#else
# define PHTREAD_TO_UI64(thr) ((PHYSFS_uint64) (thr))
#endif
PHYSFS_uint64 __PHYSFS_platformGetThreadID(void)
{
return(PHTREAD_TO_UI64(pthread_self()));
} /* __PHYSFS_platformGetThreadID */
void *__PHYSFS_platformCreateMutex(void)
{
int rc;
PthreadMutex *m = (PthreadMutex *) allocator.Malloc(sizeof (PthreadMutex));
BAIL_IF_MACRO(m == NULL, ERR_OUT_OF_MEMORY, NULL);
rc = pthread_mutex_init(&m->mutex, NULL);
if (rc != 0)
{
allocator.Free(m);
BAIL_MACRO(strerror(rc), NULL);
} /* if */
m->count = 0;
m->owner = (pthread_t) 0xDEADBEEF;
return((void *) m);
} /* __PHYSFS_platformCreateMutex */
void __PHYSFS_platformDestroyMutex(void *mutex)
{
PthreadMutex *m = (PthreadMutex *) mutex;
/* Destroying a locked mutex is a bug, but we'll try to be helpful. */
if ((m->owner == pthread_self()) && (m->count > 0))
pthread_mutex_unlock(&m->mutex);
pthread_mutex_destroy(&m->mutex);
allocator.Free(m);
} /* __PHYSFS_platformDestroyMutex */
int __PHYSFS_platformGrabMutex(void *mutex)
{
PthreadMutex *m = (PthreadMutex *) mutex;
pthread_t tid = pthread_self();
if (m->owner != tid)
{
if (pthread_mutex_lock(&m->mutex) != 0)
return(0);
m->owner = tid;
} /* if */
m->count++;
return(1);
} /* __PHYSFS_platformGrabMutex */
void __PHYSFS_platformReleaseMutex(void *mutex)
{
PthreadMutex *m = (PthreadMutex *) mutex;
if (m->owner == pthread_self())
{
if (--m->count == 0)
{
m->owner = (pthread_t) 0xDEADBEEF;
pthread_mutex_unlock(&m->mutex);
} /* if */
} /* if */
} /* __PHYSFS_platformReleaseMutex */
#endif /* !PHYSFS_NO_THREAD_SUPPORT */
#endif /* PHYSFS_PLATFORM_UNIX */
/* end of unix.c ... */