paulo@0: /*
paulo@0: ljpath - functions to support an application that can be
paulo@0: installed to either a read-write folder ("portable" config)
paulo@0: or to a read-only folder ("installed" config)
paulo@0: 
paulo@0: Copyright 2008 Damian Yerrick
paulo@0: 
paulo@0: Insert zlib license here.
paulo@0: 
paulo@0: */
paulo@0: 
paulo@0: 
paulo@0: #include <stdlib.h>
paulo@0: #include <string.h>
paulo@0: #include "ljpath.h"
paulo@0: #include <limits.h>  // for PATH_MAX
paulo@0: #include <sys/stat.h>  // for mkdir()
paulo@0: #include <errno.h>
paulo@0: 
paulo@0: #ifdef WIN32
paulo@0: #include <shlobj.h>
paulo@0: #include <direct.h>
paulo@0: #define USE_WINDOWS_APPDATA
paulo@0: #endif
paulo@0: 
paulo@0: // on the DS
paulo@0: #ifdef ARM9
paulo@0: #include <fat.h>  // Chishm's libfat
paulo@0: static char hasFAT;
paulo@0: #include <unistd.h>  // for MAXPATHLEN
paulo@0: #else
paulo@0: #define hasFAT 1
paulo@0: #endif
paulo@0: 
paulo@0: // http://forum.gbadev.org/viewtopic.php?p=147795#147795
paulo@0: #if !defined(PATH_MAX) && defined(MAXPATHLEN)
paulo@0: #define PATH_MAX MAXPATHLEN
paulo@0: #endif
paulo@0: 
paulo@0: static char readWriteFolder[PATH_MAX];
paulo@0: static char skinFolder[PATH_MAX];
paulo@0: static char readOnlyFolder[PATH_MAX];
paulo@0: 
paulo@0: 
paulo@0: #ifdef WIN32
paulo@0: static int ljmkdir(const char *path) {
paulo@0:   //allegro_message("mkdir(\"%s\")\n", path);
paulo@0:   return _mkdir(path);
paulo@0: }
paulo@0: #else
paulo@0: static int ljmkdir(const char *path) {
paulo@0:   //allegro_message("mkdir(\"%s\")\n", path);
paulo@0:   return mkdir(path, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
paulo@0: }
paulo@0: #endif
paulo@0: 
paulo@0: /**
paulo@0:  * Wrapper around mkdir() that doesn't error if the
paulo@0:  * directory already exists.
paulo@0:  */
paulo@0: static int makeFolder(const char *path) {
paulo@0:   if (ljmkdir(path) < 0) {
paulo@0:     if (errno != EEXIST) {
paulo@0:       return -1;
paulo@0:     } 
paulo@0:   }
paulo@0:   return 0;
paulo@0: }
paulo@0: 
paulo@0: 
paulo@0: 
paulo@0: /**
paulo@0:  * Computes the name of the folder containing filename.
paulo@0:  * @param dst destination to receive the folder name, of size PATH_MAX
paulo@0:  * @param filename name of a file in this folder
paulo@0:  */
paulo@0: static void ljpathSetFolder(char *dst, const char *filename) {
paulo@0:   const char *lastPathSep = NULL;
paulo@0: 
paulo@0:   // I considered strrchr, but it would need two passes:
paulo@0:   // one for '/' and one for the drive-letter ':' under Windows.
paulo@0:   for (const char *here = filename; *here != 0; ++here) {
paulo@0:     if (*here == '/' || *here == '\\' || *here == ':') {
paulo@0:       lastPathSep = here;
paulo@0:     }
paulo@0:   }
paulo@0:   if (lastPathSep == NULL || lastPathSep - filename > PATH_MAX - 1) {
paulo@0:     strcpy(dst, ".");
paulo@0:   } else {
paulo@0:     memcpy(dst, filename, lastPathSep - filename);
paulo@0:     dst[lastPathSep - filename] = 0;
paulo@0:   }
paulo@0: }
paulo@0: 
paulo@0: #if defined(USE_WINDOWS_APPDATA)
paulo@0: /**
paulo@0:  * Retrieves the read/write path on a Windows system.
paulo@0:  * SHGetFolderPath() is described in
paulo@0:  * http://msdn.microsoft.com/library/default.asp?url=/library/en-us/shellcc/platform/shell/reference/functions/shgetfolderpath.asp
paulo@0:  */
paulo@0: static void ljpathSetRWFolder(void) {
paulo@0:   static const char suffix1[] = "/Pin Eight";
paulo@0:   static const char suffix2[] = "/lockjaw";
paulo@0:   char path[MAX_PATH + sizeof(suffix1) + sizeof(suffix2)] = "";
paulo@0:   
paulo@0:   int rVal = SHGetFolderPath(      
paulo@0:     NULL,  // owner window used with obscure dial-up functionality
paulo@0:     CSIDL_APPDATA,  // type of folder to retrieve
paulo@0:     NULL,  // user ID when impersonating another user
paulo@0:     0,  // get the current path, not the default path
paulo@0:     path
paulo@0:   );
paulo@0:   if (rVal) {
paulo@0:     return;
paulo@0:   }
paulo@0: 
paulo@0:   strcat(path, suffix1);
paulo@0:   ljmkdir(path);
paulo@0:   strcat(path, suffix2);
paulo@0:   ljmkdir(path);
paulo@0:   if (strlen(path) >= PATH_MAX) {
paulo@0:     return;
paulo@0:   }
paulo@0: 
paulo@0:   strncpy(readWriteFolder, path, PATH_MAX - 1);
paulo@0:   readWriteFolder[PATH_MAX - 1] = 0;
paulo@0: }
paulo@0: #else
paulo@0: /**
paulo@0:  * Retrieves the read/write path on a UNIX system using the HOME
paulo@0:  * environment variable.
paulo@0:  */
paulo@0: static void ljpathSetRWFolder(void) {
paulo@0:   static const char suffix[] = "/.lockjaw";
paulo@0:   const char *value = getenv("HOME");
paulo@0:   if (!value) {
paulo@0:     return;
paulo@0:   }
paulo@0:   
paulo@0:   unsigned int len = strlen(value) + sizeof(suffix);
paulo@0:   if (len > PATH_MAX) {
paulo@0:     return;
paulo@0:   }
paulo@0:   
paulo@0:   strcpy(readWriteFolder, value);
paulo@0:   strcat(readWriteFolder, suffix);
paulo@0:   ljmkdir(readWriteFolder);
paulo@0:   //allegro_message("readWriteFolder is now \"%s\"\n", skinFolder);
paulo@0: }
paulo@0: #endif
paulo@0: 
paulo@0: void ljpathSetSkinFolder(const char *filename) {
paulo@0:   //allegro_message("ljpathSetFolder(skinFolder, \"%s\")\n", filename);
paulo@0:   ljpathSetFolder(skinFolder, filename);
paulo@0:   //allegro_message("skinFolder is now \"%s\"\n", skinFolder);
paulo@0: }
paulo@0: 
paulo@0: static int ljpathJoin(char *restrict dst,
paulo@0:                       const char *restrict folder,
paulo@0:                       const char *restrict filename) {
paulo@0:   size_t len = 0;
paulo@0: 
paulo@0:   //allegro_message("ljpathJoin(\"%s\", \"%s\")\n", folder, filename);
paulo@0: 
paulo@0:   // If the path is not absolute, copy the folder and the
paulo@0:   // path separator into the destination string.
paulo@0:   if (filename[0] != '\\' && filename[0] != '\\'
paulo@0:       && filename[1] != ':') {
paulo@0:     while (len < PATH_MAX - 1 && *folder != 0) {
paulo@0:       dst[len++] = *folder++;
paulo@0:     }
paulo@0:     /* The path separator '/' is standard under Linux and Mac OS X.
paulo@0:        It also works on MS-DOS and Windows API, notwithstanding 
paulo@0:        certain Microsoft command-line utilities. */
paulo@0:     dst[len++] = '/';
paulo@0:     while (len < PATH_MAX - 1 && *filename != 0) {
paulo@0:       dst[len++] = *filename++;
paulo@0:     }
paulo@0:   }
paulo@0: 
paulo@0:   if (len < PATH_MAX - 1) {
paulo@0:     dst[len] = 0;
paulo@0:     //allegro_message("equals \"%s\"\n", dst);
paulo@0:     return 1;
paulo@0:   }
paulo@0:   //allegro_message("failed\n");
paulo@0:   return 0;
paulo@0: }
paulo@0: 
paulo@0: /**
paulo@0:  * Determines whether a file exists and is readable.
paulo@0:  * @param path the path of a file
paulo@0:  * @return nonzero iff readable
paulo@0:  */
paulo@0: static int fexists(const char *path) {
paulo@0:   struct stat st;
paulo@0:   if (!hasFAT) {
paulo@0:     return 0;
paulo@0:   }
paulo@0:   int rval = stat(path, &st);
paulo@0:   //allegro_message("stat(\"%s\") returned %d\n", path, rval);
paulo@0:   return rval == 0;
paulo@0: }
paulo@0: 
paulo@0: int ljpathInit(const char *argv0) {
paulo@0: #ifdef ARM9
paulo@0:   hasFAT = fatInitDefault();
paulo@0:   if (hasFAT) {
paulo@0:     if (makeFolder("/data") < 0 || makeFolder("/data/lockjaw") < 0) {
paulo@0:       hasFAT = 0;
paulo@0:     }
paulo@0:   }
paulo@0:   strcpy(readOnlyFolder, "/data/lockjaw");
paulo@0:   strcpy(readWriteFolder, "/data/lockjaw");
paulo@0:   strcpy(skinFolder, "/data/lockjaw");
paulo@0:   return hasFAT;
paulo@0: #else
paulo@0:   char path[PATH_MAX];
paulo@0:   int installed;
paulo@0: 
paulo@0:   //allegro_message("argv[0] = \"%s\"", argv0);
paulo@0:   ljpathSetFolder(readOnlyFolder, argv0);
paulo@0:   strcpy(readWriteFolder, ".");
paulo@0:   strcpy(skinFolder, ".");
paulo@0: 
paulo@0:   // determine whether "installed.ini" (an empty text file)
paulo@0:   // exists
paulo@0:   installed = ljpathJoin(path, readOnlyFolder, "installed.ini") >= 0 
paulo@0:               && fexists(path);
paulo@0:   if (installed) {
paulo@0:     ljpathSetRWFolder();
paulo@0:   }
paulo@0:   return installed;
paulo@0: #endif
paulo@0: }
paulo@0: 
paulo@0: /**
paulo@0:  * Finds a file name for reading.
paulo@0:  * @param dst buffer for path, of size PATH_MAX
paulo@0:  * @param src name of file
paulo@0:  * @return 0 if not found, nonzero if found
paulo@0:  */
paulo@0: int ljpathFind_r(char *restrict dst, const char *restrict filename) {
paulo@0:   if (!hasFAT) {
paulo@0:     return 0;
paulo@0:   }
paulo@0:   if (ljpathJoin(dst, readWriteFolder, filename) >= 0 
paulo@0:       && fexists(dst)) {
paulo@0:     return 1;
paulo@0:   }
paulo@0:   if (ljpathJoin(dst, skinFolder, filename) >= 0 
paulo@0:       && fexists(dst)) {
paulo@0:     return 1;
paulo@0:   }
paulo@0:   if (ljpathJoin(dst, readOnlyFolder, filename) >= 0 
paulo@0:       && fexists(dst)) {
paulo@0:     return 1;
paulo@0:   }
paulo@0:   return 0;
paulo@0: }
paulo@0: 
paulo@0: int ljpathFind_w(char *restrict dst, const char *restrict filename) {
paulo@0:   return ljpathJoin(dst, readWriteFolder, filename);
paulo@0: }
paulo@0: 
paulo@0: FILE *ljfopen(const char *restrict filename, const char *restrict mode) {
paulo@0:   char path[PATH_MAX];
paulo@0:   FILE *fp;
paulo@0:   
paulo@0:   if (!hasFAT) {
paulo@0:     return NULL;
paulo@0:   }
paulo@0: 
paulo@0:   //allegro_message("ljfopen(\"%s\", \"%s\")\n", filename, mode);
paulo@0:   if (mode[0] == 'r') {
paulo@0: 
paulo@0:     // For read-only files, search all three paths.
paulo@0:     if (ljpathFind_r(path, filename) >= 0 
paulo@0:         && (fp = fopen(path, mode)) != 0) {
paulo@0:       //allegro_message("fopen(\"%s\", \"%s\") for reading\n", path, mode);
paulo@0:       return fp;
paulo@0:     }
paulo@0:   } else {
paulo@0: 
paulo@0:     // For read/write files, check only the read/write path.
paulo@0:     if (ljpathFind_w(path, filename) >= 0 
paulo@0:         && (fp = fopen(path, mode)) != 0) {
paulo@0:       //allegro_message("fopen(\"%s\", \"%s\") for writing\n", path, mode);
paulo@0:       return fp;
paulo@0:     }
paulo@0:   }
paulo@0:   return NULL;
paulo@0: }
paulo@0: