SDL_sysfilesystem.c
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/*
Simple DirectMedia Layer
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"
#ifdef SDL_FILESYSTEM_UNIX
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/* System dependent filesystem routines */
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <limits.h>
#ifdef __FREEBSD__
#include <sys/sysctl.h>
#endif
#include "SDL_error.h"
#include "SDL_stdinc.h"
#include "SDL_filesystem.h"
static char *
readSymLink(const char *path)
{
char *retval = NULL;
ssize_t len = 64;
ssize_t rc = -1;
while (1)
{
char *ptr = (char *) SDL_realloc(retval, (size_t) len);
if (ptr == NULL) {
SDL_OutOfMemory();
break;
}
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. */
}
len *= 2; /* grow buffer, try again. */
}
SDL_free(retval);
return NULL;
}
char *
SDL_GetBasePath(void)
{
char *retval = NULL;
#if defined(__FREEBSD__)
char fullpath[PATH_MAX];
size_t buflen = sizeof (fullpath);
const int mib[] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
if (sysctl(mib, SDL_arraysize(mib), fullpath, &buflen, NULL, 0) != -1) {
retval = SDL_strdup(fullpath);
if (!retval) {
SDL_OutOfMemory();
return NULL;
}
}
#elif defined(__SOLARIS__)
const char *path = getexecname();
if ((path != NULL) && (path[0] == '/')) { /* must be absolute path... */
retval = SDL_strdup(path);
if (!retval) {
SDL_OutOfMemory();
return NULL;
}
}
#endif
/* is a Linux-style /proc filesystem available? */
if (!retval && (access("/proc", F_OK) == 0)) {
#if defined(__FREEBSD__)
retval = readSymLink("/proc/curproc/file");
#elif defined(__NETBSD__)
retval = readSymLink("/proc/curproc/exe");
#else
retval = readSymLink("/proc/self/exe"); /* linux. */
#endif
if (retval == NULL) {
/* older kernels don't have /proc/self ... try PID version... */
char path[64];
const int rc = (int) SDL_snprintf(path, sizeof(path),
"/proc/%llu/exe",
(unsigned long long) getpid());
if ( (rc > 0) && (rc < sizeof(path)) ) {
retval = readSymLink(path);
}
}
}
/* If we had access to argv[0] here, we could check it for a path,
or troll through $PATH looking for it, too. */
if (retval != NULL) { /* chop off filename. */
char *ptr = SDL_strrchr(retval, '/');
if (ptr != NULL) {
*(ptr+1) = '\0';
} else { /* shouldn't happen, but just in case... */
SDL_free(retval);
retval = NULL;
}
}
if (retval != NULL) {
/* try to shrink buffer... */
char *ptr = (char *) SDL_realloc(retval, strlen(retval) + 1);
if (ptr != NULL)
retval = ptr; /* oh well if it failed. */
}
return retval;
}
char *
SDL_GetPrefPath(const char *org, const char *app)
{
/*
* We use XDG's base directory spec, even if you're not on Linux.
* This isn't strictly correct, but the results are relatively sane
* in any case.
*
* http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
*/
const char *envr = SDL_getenv("XDG_DATA_HOME");
const char *append;
char *retval = NULL;
char *ptr = NULL;
size_t len = 0;
if (!envr) {
/* You end up with "$HOME/.local/share/Game Name 2" */
envr = SDL_getenv("HOME");
if (!envr) {
/* we could take heroic measures with /etc/passwd, but oh well. */
SDL_SetError("neither XDG_DATA_HOME nor HOME environment is set");
return NULL;
}
append = "/.local/share/";
} else {
append = "/";
}
len = SDL_strlen(envr);
if (envr[len - 1] == '/')
append += 1;
len += SDL_strlen(append) + SDL_strlen(org) + SDL_strlen(app) + 3;
retval = (char *) SDL_malloc(len);
if (!retval) {
SDL_OutOfMemory();
return NULL;
}
SDL_snprintf(retval, len, "%s%s%s/%s/", envr, append, org, app);
for (ptr = retval+1; *ptr; ptr++) {
if (*ptr == '/') {
*ptr = '\0';
if (mkdir(retval, 0700) != 0 && errno != EEXIST)
goto error;
*ptr = '/';
}
}
if (mkdir(retval, 0700) != 0 && errno != EEXIST) {
error:
SDL_SetError("Couldn't create directory '%s': '%s'", retval, strerror(errno));
SDL_free(retval);
return NULL;
}
return retval;
}
#endif /* SDL_FILESYSTEM_UNIX */
/* vi: set ts=4 sw=4 expandtab: */
SDL_realloc
#define SDL_realloc
Definition: SDL_dynapi_overrides.h:382
len
GLenum GLsizei len
Definition: SDL_opengl_glext.h:2926
access
GLuint GLint GLboolean GLint GLenum access
Definition: SDL_opengl_glext.h:2162
retval
SDL_bool retval
Definition: testgamecontroller.c:65
SDL_free
void SDL_free(void *mem)
SDL_getenv
#define SDL_getenv
Definition: SDL_dynapi_overrides.h:384
NULL
#define NULL
Definition: begin_code.h:143
SDL_OutOfMemory
#define SDL_OutOfMemory()
Definition: SDL_error.h:52
SDL_SetError
#define SDL_SetError
Definition: SDL_dynapi_overrides.h:36
SDL_stdinc.h
SDL_strlen
#define SDL_strlen
Definition: SDL_dynapi_overrides.h:399
SDL_strdup
#define SDL_strdup
Definition: SDL_dynapi_overrides.h:403
SDL_GetPrefPath
#define SDL_GetPrefPath
Definition: SDL_dynapi_overrides.h:140
SDL_filesystem.h
Include file for filesystem SDL API functions.
SDL_snprintf
#define SDL_snprintf
Definition: SDL_dynapi_overrides.h:46
SDL_arraysize
#define SDL_arraysize(array)
Definition: SDL_stdinc.h:93
SDL_malloc
#define SDL_malloc
Definition: SDL_dynapi_overrides.h:380
path
GLsizei const GLchar *const * path
Definition: SDL_opengl_glext.h:3730
SDL_GetBasePath
char * SDL_GetBasePath(void)
Get the path where the application resides.
SDL_strrchr
#define SDL_strrchr
Definition: SDL_dynapi_overrides.h:408
SDL_error.h