Guido van Rossum | 1aa7e3a | 1997-05-19 14:16:21 +0000 | [diff] [blame^] | 1 | /*********************************************************** |
| 2 | Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam, |
| 3 | The Netherlands. |
| 4 | |
| 5 | All Rights Reserved |
| 6 | |
| 7 | Permission to use, copy, modify, and distribute this software and its |
| 8 | documentation for any purpose and without fee is hereby granted, |
| 9 | provided that the above copyright notice appear in all copies and that |
| 10 | both that copyright notice and this permission notice appear in |
| 11 | supporting documentation, and that the names of Stichting Mathematisch |
| 12 | Centrum or CWI or Corporation for National Research Initiatives or |
| 13 | CNRI not be used in advertising or publicity pertaining to |
| 14 | distribution of the software without specific, written prior |
| 15 | permission. |
| 16 | |
| 17 | While CWI is the initial source for this software, a modified version |
| 18 | is made available by the Corporation for National Research Initiatives |
| 19 | (CNRI) at the Internet address ftp://ftp.python.org. |
| 20 | |
| 21 | STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH |
| 22 | REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF |
| 23 | MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH |
| 24 | CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL |
| 25 | DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR |
| 26 | PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER |
| 27 | TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR |
| 28 | PERFORMANCE OF THIS SOFTWARE. |
| 29 | |
| 30 | ******************************************************************/ |
| 31 | |
| 32 | /* Return the initial module search path. */ |
| 33 | /* Used by DOS, OS/2, Windows 3.1. Works on NT too. */ |
| 34 | |
| 35 | #include "Python.h" |
| 36 | #include "osdefs.h" |
| 37 | |
| 38 | #include <sys/types.h> |
| 39 | #include <sys/stat.h> |
| 40 | #include <string.h> |
| 41 | |
| 42 | #if HAVE_UNISTD_H |
| 43 | #include <unistd.h> |
| 44 | #endif /* HAVE_UNISTD_H */ |
| 45 | |
| 46 | /* Search in some common locations for the associated Python libraries. |
| 47 | * |
| 48 | * This version always returns "" for both prefix and exec_prefix. |
| 49 | * |
| 50 | * Py_GetPath() tries to return a sensible Python module search path. |
| 51 | * |
| 52 | * First, we look to see if the executable is in a subdirectory of |
| 53 | * the Python build directory. We calculate the full path of the |
| 54 | * directory containing the executable as progpath. We work backwards |
| 55 | * along progpath and look for $dir/Modules/Setup.in, a distinctive |
| 56 | * landmark. If found, we use $dir/Lib as $root. The returned |
| 57 | * Python path is the compiled #define PYTHONPATH with all the initial |
| 58 | * "./lib" replaced by $root. |
| 59 | * |
| 60 | * Otherwise, if there is a PYTHONPATH environment variable, we return that. |
| 61 | * |
| 62 | * Otherwise we try to find $progpath/lib/string.py, and if found, then |
| 63 | * root is $progpath/lib, and we return Python path as compiled PYTHONPATH |
| 64 | * with all "./lib" replaced by $root (as above). |
| 65 | * |
| 66 | */ |
| 67 | |
| 68 | #ifndef LANDMARK |
| 69 | #define LANDMARK "Modules\\Setup.in" |
| 70 | #endif |
| 71 | |
| 72 | static char prefix[MAXPATHLEN+1]; |
| 73 | static char progpath[MAXPATHLEN+1]; |
| 74 | static char *module_search_path = NULL; |
| 75 | |
| 76 | static int |
| 77 | is_sep(ch) /* determine if "ch" is a separator character */ |
| 78 | char ch; |
| 79 | { |
| 80 | #ifdef ALTSEP |
| 81 | return ch == SEP || ch == ALTSEP; |
| 82 | #else |
| 83 | return ch == SEP; |
| 84 | #endif |
| 85 | } |
| 86 | |
| 87 | static void |
| 88 | reduce(dir) |
| 89 | char *dir; |
| 90 | { |
| 91 | int i = strlen(dir); |
| 92 | while (i > 0 && !is_sep(dir[i])) |
| 93 | --i; |
| 94 | dir[i] = '\0'; |
| 95 | } |
| 96 | |
| 97 | |
| 98 | static int |
| 99 | exists(filename) |
| 100 | char *filename; |
| 101 | { |
| 102 | struct stat buf; |
| 103 | return stat(filename, &buf) == 0; |
| 104 | } |
| 105 | |
| 106 | |
| 107 | static void |
| 108 | join(buffer, stuff) |
| 109 | char *buffer; |
| 110 | char *stuff; |
| 111 | { |
| 112 | int n, k; |
| 113 | if (is_sep(stuff[0])) |
| 114 | n = 0; |
| 115 | else { |
| 116 | n = strlen(buffer); |
| 117 | if (n > 0 && !is_sep(buffer[n-1]) && n < MAXPATHLEN) |
| 118 | buffer[n++] = SEP; |
| 119 | } |
| 120 | k = strlen(stuff); |
| 121 | if (n + k > MAXPATHLEN) |
| 122 | k = MAXPATHLEN - n; |
| 123 | strncpy(buffer+n, stuff, k); |
| 124 | buffer[n+k] = '\0'; |
| 125 | } |
| 126 | |
| 127 | |
| 128 | static int |
| 129 | search_for_prefix(argv0_path, landmark) |
| 130 | char *argv0_path; |
| 131 | char *landmark; |
| 132 | { |
| 133 | int n; |
| 134 | |
| 135 | /* Search from argv0_path, until root is found */ |
| 136 | strcpy(prefix, argv0_path); |
| 137 | do { |
| 138 | n = strlen(prefix); |
| 139 | join(prefix, landmark); |
| 140 | if (exists(prefix)) |
| 141 | return 1; |
| 142 | prefix[n] = '\0'; |
| 143 | reduce(prefix); |
| 144 | } while (prefix[0]); |
| 145 | return 0; |
| 146 | } |
| 147 | |
| 148 | static void |
| 149 | get_progpath() |
| 150 | { |
| 151 | #ifdef MS_WIN32 |
| 152 | #include <windows.h> |
| 153 | if (!GetModuleFileName(NULL, progpath, MAXPATHLEN)) |
| 154 | progpath[0] = '\0'; /* failure */ |
| 155 | #else |
| 156 | extern char *Py_GetProgramName(); |
| 157 | char *path = getenv("PATH"); |
| 158 | char *prog = Py_GetProgramName(); |
| 159 | |
| 160 | /* If there is no slash in the argv0 path, then we have to |
| 161 | * assume python is on the user's $PATH, since there's no |
| 162 | * other way to find a directory to start the search from. If |
| 163 | * $PATH isn't exported, you lose. |
| 164 | */ |
| 165 | #ifdef ALTSEP |
| 166 | if (strchr(prog, SEP) || strchr(prog, ALTSEP)) |
| 167 | #else |
| 168 | if (strchr(prog, SEP)) |
| 169 | #endif |
| 170 | strcpy(progpath, prog); |
| 171 | else if (path) { |
| 172 | while (1) { |
| 173 | char *delim = strchr(path, DELIM); |
| 174 | |
| 175 | if (delim) { |
| 176 | int len = delim - path; |
| 177 | strncpy(progpath, path, len); |
| 178 | *(progpath + len) = '\0'; |
| 179 | } |
| 180 | else |
| 181 | strcpy(progpath, path); |
| 182 | |
| 183 | join(progpath, prog); |
| 184 | if (exists(progpath)) |
| 185 | break; |
| 186 | |
| 187 | if (!delim) { |
| 188 | progpath[0] = '\0'; |
| 189 | break; |
| 190 | } |
| 191 | path = delim + 1; |
| 192 | } |
| 193 | } |
| 194 | else |
| 195 | progpath[0] = '\0'; |
| 196 | #endif |
| 197 | } |
| 198 | |
| 199 | static void |
| 200 | calculate_path() |
| 201 | { |
| 202 | char ch, *pt, *pt2; |
| 203 | char argv0_path[MAXPATHLEN+1]; |
| 204 | char *buf; |
| 205 | int bufsz; |
| 206 | |
| 207 | get_progpath(); |
| 208 | strcpy(argv0_path, progpath); |
| 209 | reduce(argv0_path); |
| 210 | |
| 211 | if (search_for_prefix(argv0_path, LANDMARK)) { |
| 212 | reduce(prefix); |
| 213 | reduce(prefix); |
| 214 | join(prefix, "lib"); |
| 215 | } |
| 216 | else if ((module_search_path = getenv("PYTHONPATH")) != 0) { |
| 217 | return; /* if PYTHONPATH environment variable exists, we are done */ |
| 218 | } |
| 219 | else { /* Try the executable_directory/lib */ |
| 220 | strcpy(prefix, progpath); |
| 221 | reduce(prefix); |
| 222 | join(prefix, "lib"); |
| 223 | join(prefix, "string.py"); /* Look for lib/string.py */ |
| 224 | if (exists(prefix)) { |
| 225 | reduce(prefix); |
| 226 | } |
| 227 | else { /* No module search path!!! */ |
| 228 | module_search_path = PYTHONPATH; |
| 229 | return; |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | |
| 234 | /* If we get here, we need to return a path equal to the compiled |
| 235 | PYTHONPATH with ".\lib" replaced by our "prefix" directory */ |
| 236 | |
| 237 | bufsz = 1; /* Calculate size of return buffer. */ |
| 238 | for (pt = PYTHONPATH; *pt; pt++) |
| 239 | if (*pt == DELIM) |
| 240 | bufsz++; /* number of DELIM plus one */ |
| 241 | bufsz *= strlen(PYTHONPATH) + strlen(prefix); /* high estimate */ |
| 242 | |
| 243 | module_search_path = buf = malloc(bufsz); |
| 244 | |
| 245 | if (buf == NULL) { |
| 246 | /* We can't exit, so print a warning and limp along */ |
| 247 | fprintf(stderr, "Not enough memory for dynamic PYTHONPATH.\n"); |
| 248 | fprintf(stderr, "Using default static PYTHONPATH.\n"); |
| 249 | module_search_path = PYTHONPATH; |
| 250 | return; |
| 251 | } |
| 252 | for (pt = PYTHONPATH; *pt; pt++) { |
| 253 | if (!strncmp(pt, ".\\lib", 5) && |
| 254 | ((ch = *(pt + 5)) == '\\' || ch == DELIM || !ch)){ |
| 255 | pt += 4; |
| 256 | for (pt2 = prefix; *pt2; pt2++) |
| 257 | *buf++ = *pt2; |
| 258 | } |
| 259 | else |
| 260 | *buf++ = *pt; |
| 261 | } |
| 262 | *buf = '\0'; |
| 263 | } |
| 264 | |
| 265 | |
| 266 | /* External interface */ |
| 267 | |
| 268 | char * |
| 269 | Py_GetPath() |
| 270 | { |
| 271 | if (!module_search_path) |
| 272 | calculate_path(); |
| 273 | return module_search_path; |
| 274 | } |
| 275 | |
| 276 | char * |
| 277 | Py_GetPrefix() |
| 278 | { |
| 279 | return ""; |
| 280 | } |
| 281 | |
| 282 | char * |
| 283 | Py_GetExecPrefix() |
| 284 | { |
| 285 | return ""; |
| 286 | } |
| 287 | |
| 288 | char * |
| 289 | Py_GetProgramFullPath() /* Full path to Python executable */ |
| 290 | { |
| 291 | if (!module_search_path) |
| 292 | calculate_path(); |
| 293 | return progpath; |
| 294 | } |