src/platform_unix.c
changeset 972 254427fc42ab
parent 889 0364fa566f29
child 987 ae7b616e7d0e
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/platform_unix.c	Fri Mar 27 15:10:42 2009 -0400
@@ -0,0 +1,395 @@
+/*
+ * 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>
+#include <sys/mount.h>
+
+#if (!defined PHYSFS_NO_PTHREADS_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>
+#endif
+
+#ifdef PHYSFS_HAVE_MNTENT_H
+#include <mntent.h>
+#endif
+
+#include "physfs_internal.h"
+
+
+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;
+
+        /* 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 */
+
+
+char *__PHYSFS_platformCalcBaseDir(const char *argv0)
+{
+    const char *PROC_SELF_EXE = "/proc/self/exe";
+    char *retval = NULL;
+    char *envr = NULL;
+    struct stat stbuf;
+
+    /* 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.
+     */
+    if ((lstat(PROC_SELF_EXE, &stbuf) != -1) && (S_ISLNK(stbuf.st_mode)))
+    {
+        const size_t len = stbuf.st_size;
+        char *buf = (char *) allocator.Malloc(len+1);
+        if (buf != NULL)  /* if NULL, maybe you'll get lucky later. */
+        {
+            if (readlink(PROC_SELF_EXE, buf, len) != len)
+                allocator.Free(buf);
+            else
+            {
+                buf[len] = '\0';  /* readlink doesn't null-terminate. */
+                retval = buf;  /* we're good to go. */
+            } /* else */
+        } /* if */
+    } /* 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 */
+
+    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_PTHREADS_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_PTHREADS_SUPPORT */
+
+#endif /* PHYSFS_PLATFORM_UNIX */
+
+/* end of unix.c ... */
+