Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 1 | |
| 2 | /* Return the initial module search path. */ |
| 3 | /* This version used by OS/2+EMX */ |
| 4 | |
| 5 | /* ---------------------------------------------------------------- |
| 6 | PATH RULES FOR OS/2+EMX: |
| 7 | This describes how sys.path is formed on OS/2+EMX. It describes the |
| 8 | functionality, not the implementation (ie, the order in which these |
| 9 | are actually fetched is different) |
| 10 | |
| 11 | * Python always adds an empty entry at the start, which corresponds |
| 12 | to the current directory. |
| 13 | |
Georg Brandl | 7eb4b7d | 2005-07-22 21:49:32 +0000 | [diff] [blame] | 14 | * If the PYTHONPATH env. var. exists, its entries are added next. |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 15 | |
| 16 | * We attempt to locate the "Python Home" - if the PYTHONHOME env var |
| 17 | is set, we believe it. Otherwise, we use the path of our host .EXE's |
| 18 | to try and locate our "landmark" (lib\\os.py) and deduce our home. |
| 19 | - If we DO have a Python Home: The relevant sub-directories (Lib, |
| 20 | plat-win, lib-tk, etc) are based on the Python Home |
| 21 | - If we DO NOT have a Python Home, the core Python Path is |
| 22 | loaded from the registry. This is the main PythonPath key, |
| 23 | and both HKLM and HKCU are combined to form the path) |
| 24 | |
| 25 | * Iff - we can not locate the Python Home, and have not had a PYTHONPATH |
| 26 | specified (ie, we have _nothing_ we can assume is a good path), a |
| 27 | default path with relative entries is used (eg. .\Lib;.\plat-win, etc) |
| 28 | |
| 29 | |
| 30 | The end result of all this is: |
| 31 | * When running python.exe, or any other .exe in the main Python directory |
| 32 | (either an installed version, or directly from the PCbuild directory), |
| 33 | the core path is deduced. |
| 34 | |
| 35 | * When Python is hosted in another exe (different directory, embedded via |
| 36 | COM, etc), the Python Home will not be deduced, so the core path from |
| 37 | the registry is used. Other "application paths "in the registry are |
| 38 | always read. |
| 39 | |
| 40 | * If Python can't find its home and there is no registry (eg, frozen |
| 41 | exe, some very strange installation setup) you get a path with |
| 42 | some default, but relative, paths. |
| 43 | |
| 44 | ---------------------------------------------------------------- */ |
| 45 | |
| 46 | |
| 47 | #include "Python.h" |
| 48 | #include "osdefs.h" |
| 49 | |
| 50 | #ifndef PYOS_OS2 |
| 51 | #error This file only compilable on OS/2 |
| 52 | #endif |
| 53 | |
| 54 | #define INCL_DOS |
| 55 | #include <os2.h> |
| 56 | |
| 57 | #include <sys/types.h> |
| 58 | #include <sys/stat.h> |
| 59 | #include <string.h> |
| 60 | |
| 61 | #if HAVE_UNISTD_H |
| 62 | #include <unistd.h> |
| 63 | #endif /* HAVE_UNISTD_H */ |
| 64 | |
| 65 | /* Search in some common locations for the associated Python libraries. |
| 66 | * |
| 67 | * Py_GetPath() tries to return a sensible Python module search path. |
| 68 | * |
| 69 | * The approach is an adaptation for Windows of the strategy used in |
| 70 | * ../Modules/getpath.c; it uses the Windows Registry as one of its |
| 71 | * information sources. |
| 72 | */ |
| 73 | |
| 74 | #ifndef LANDMARK |
| 75 | #if defined(PYCC_GCC) |
| 76 | #define LANDMARK "lib/os.py" |
| 77 | #else |
| 78 | #define LANDMARK "lib\\os.py" |
| 79 | #endif |
| 80 | #endif |
| 81 | |
| 82 | static char prefix[MAXPATHLEN+1]; |
| 83 | static char progpath[MAXPATHLEN+1]; |
| 84 | static char *module_search_path = NULL; |
| 85 | |
| 86 | |
| 87 | static int |
| 88 | is_sep(char ch) /* determine if "ch" is a separator character */ |
| 89 | { |
| 90 | #ifdef ALTSEP |
| 91 | return ch == SEP || ch == ALTSEP; |
| 92 | #else |
| 93 | return ch == SEP; |
| 94 | #endif |
| 95 | } |
| 96 | |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 97 | /* assumes 'dir' null terminated in bounds. |
| 98 | * Never writes beyond existing terminator. |
| 99 | */ |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 100 | static void |
| 101 | reduce(char *dir) |
| 102 | { |
| 103 | size_t i = strlen(dir); |
| 104 | while (i > 0 && !is_sep(dir[i])) |
| 105 | --i; |
| 106 | dir[i] = '\0'; |
| 107 | } |
| 108 | |
| 109 | static int |
| 110 | exists(char *filename) |
| 111 | { |
| 112 | struct stat buf; |
| 113 | return stat(filename, &buf) == 0; |
| 114 | } |
| 115 | |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 116 | /* Is module (check for .pyc/.pyo too) |
| 117 | * Assumes 'filename' MAXPATHLEN+1 bytes long - |
| 118 | * may extend 'filename' by one character. |
| 119 | */ |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 120 | static int |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 121 | ismodule(char *filename) |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 122 | { |
| 123 | if (exists(filename)) |
| 124 | return 1; |
| 125 | |
| 126 | /* Check for the compiled version of prefix. */ |
| 127 | if (strlen(filename) < MAXPATHLEN) { |
| 128 | strcat(filename, Py_OptimizeFlag ? "o" : "c"); |
| 129 | if (exists(filename)) |
| 130 | return 1; |
| 131 | } |
| 132 | return 0; |
| 133 | } |
| 134 | |
Andrew MacIntyre | d0278ec | 2004-12-12 08:28:11 +0000 | [diff] [blame] | 135 | /* Add a path component, by appending stuff to buffer. |
| 136 | buffer must have at least MAXPATHLEN + 1 bytes allocated, and contain a |
| 137 | NUL-terminated string with no more than MAXPATHLEN characters (not counting |
| 138 | the trailing NUL). It's a fatal error if it contains a string longer than |
| 139 | that (callers must be careful!). If these requirements are met, it's |
| 140 | guaranteed that buffer will still be a NUL-terminated string with no more |
| 141 | than MAXPATHLEN characters at exit. If stuff is too long, only as much of |
| 142 | stuff as fits will be appended. |
| 143 | */ |
| 144 | |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 145 | static void |
| 146 | join(char *buffer, char *stuff) |
| 147 | { |
| 148 | size_t n, k; |
| 149 | if (is_sep(stuff[0])) |
| 150 | n = 0; |
| 151 | else { |
| 152 | n = strlen(buffer); |
| 153 | if (n > 0 && !is_sep(buffer[n-1]) && n < MAXPATHLEN) |
| 154 | buffer[n++] = SEP; |
| 155 | } |
Andrew MacIntyre | d0278ec | 2004-12-12 08:28:11 +0000 | [diff] [blame] | 156 | if (n > MAXPATHLEN) |
| 157 | Py_FatalError("buffer overflow in getpathp.c's joinpath()"); |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 158 | k = strlen(stuff); |
| 159 | if (n + k > MAXPATHLEN) |
| 160 | k = MAXPATHLEN - n; |
| 161 | strncpy(buffer+n, stuff, k); |
| 162 | buffer[n+k] = '\0'; |
| 163 | } |
| 164 | |
| 165 | /* gotlandmark only called by search_for_prefix, which ensures |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 166 | * 'prefix' is null terminated in bounds. join() ensures |
| 167 | * 'landmark' can not overflow prefix if too long. |
| 168 | */ |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 169 | static int |
| 170 | gotlandmark(char *landmark) |
| 171 | { |
| 172 | int n, ok; |
| 173 | |
| 174 | n = strlen(prefix); |
| 175 | join(prefix, landmark); |
| 176 | ok = ismodule(prefix); |
| 177 | prefix[n] = '\0'; |
| 178 | return ok; |
| 179 | } |
| 180 | |
| 181 | /* assumes argv0_path is MAXPATHLEN+1 bytes long, already \0 term'd. |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 182 | * assumption provided by only caller, calculate_path() |
| 183 | */ |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 184 | static int |
| 185 | search_for_prefix(char *argv0_path, char *landmark) |
| 186 | { |
| 187 | /* Search from argv0_path, until landmark is found */ |
| 188 | strcpy(prefix, argv0_path); |
| 189 | do { |
| 190 | if (gotlandmark(landmark)) |
| 191 | return 1; |
| 192 | reduce(prefix); |
| 193 | } while (prefix[0]); |
| 194 | return 0; |
| 195 | } |
| 196 | |
| 197 | |
| 198 | static void |
| 199 | get_progpath(void) |
| 200 | { |
| 201 | extern char *Py_GetProgramName(void); |
| 202 | char *path = getenv("PATH"); |
| 203 | char *prog = Py_GetProgramName(); |
| 204 | |
| 205 | PPIB pib; |
| 206 | if ((DosGetInfoBlocks(NULL, &pib) == 0) && |
| 207 | (DosQueryModuleName(pib->pib_hmte, sizeof(progpath), progpath) == 0)) |
| 208 | return; |
| 209 | |
| 210 | if (prog == NULL || *prog == '\0') |
| 211 | prog = "python"; |
| 212 | |
| 213 | /* If there is no slash in the argv0 path, then we have to |
| 214 | * assume python is on the user's $PATH, since there's no |
| 215 | * other way to find a directory to start the search from. If |
| 216 | * $PATH isn't exported, you lose. |
| 217 | */ |
| 218 | #ifdef ALTSEP |
| 219 | if (strchr(prog, SEP) || strchr(prog, ALTSEP)) |
| 220 | #else |
| 221 | if (strchr(prog, SEP)) |
| 222 | #endif |
| 223 | strncpy(progpath, prog, MAXPATHLEN); |
| 224 | else if (path) { |
| 225 | while (1) { |
| 226 | char *delim = strchr(path, DELIM); |
| 227 | |
| 228 | if (delim) { |
| 229 | size_t len = delim - path; |
| 230 | /* ensure we can't overwrite buffer */ |
| 231 | #if !defined(PYCC_GCC) |
| 232 | len = min(MAXPATHLEN,len); |
| 233 | #else |
| 234 | len = MAXPATHLEN < len ? MAXPATHLEN : len; |
| 235 | #endif |
| 236 | strncpy(progpath, path, len); |
| 237 | *(progpath + len) = '\0'; |
| 238 | } |
| 239 | else |
| 240 | strncpy(progpath, path, MAXPATHLEN); |
| 241 | |
| 242 | /* join() is safe for MAXPATHLEN+1 size buffer */ |
| 243 | join(progpath, prog); |
| 244 | if (exists(progpath)) |
| 245 | break; |
| 246 | |
| 247 | if (!delim) { |
| 248 | progpath[0] = '\0'; |
| 249 | break; |
| 250 | } |
| 251 | path = delim + 1; |
| 252 | } |
| 253 | } |
| 254 | else |
| 255 | progpath[0] = '\0'; |
| 256 | } |
| 257 | |
| 258 | static void |
| 259 | calculate_path(void) |
| 260 | { |
| 261 | char argv0_path[MAXPATHLEN+1]; |
| 262 | char *buf; |
| 263 | size_t bufsz; |
| 264 | char *pythonhome = Py_GetPythonHome(); |
| 265 | char *envpath = getenv("PYTHONPATH"); |
Andrew MacIntyre | 214d39a | 2003-01-02 12:41:58 +0000 | [diff] [blame] | 266 | char zip_path[MAXPATHLEN+1]; |
| 267 | size_t len; |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 268 | |
| 269 | get_progpath(); |
| 270 | /* progpath guaranteed \0 terminated in MAXPATH+1 bytes. */ |
| 271 | strcpy(argv0_path, progpath); |
| 272 | reduce(argv0_path); |
| 273 | if (pythonhome == NULL || *pythonhome == '\0') { |
| 274 | if (search_for_prefix(argv0_path, LANDMARK)) |
| 275 | pythonhome = prefix; |
| 276 | else |
| 277 | pythonhome = NULL; |
| 278 | } |
| 279 | else |
| 280 | strncpy(prefix, pythonhome, MAXPATHLEN); |
| 281 | |
| 282 | if (envpath && *envpath == '\0') |
| 283 | envpath = NULL; |
| 284 | |
Andrew MacIntyre | 214d39a | 2003-01-02 12:41:58 +0000 | [diff] [blame] | 285 | /* Calculate zip archive path */ |
| 286 | strncpy(zip_path, progpath, MAXPATHLEN); |
| 287 | zip_path[MAXPATHLEN] = '\0'; |
| 288 | len = strlen(zip_path); |
| 289 | if (len > 4) { |
| 290 | zip_path[len-3] = 'z'; /* change ending to "zip" */ |
| 291 | zip_path[len-2] = 'i'; |
| 292 | zip_path[len-1] = 'p'; |
| 293 | } |
| 294 | else { |
| 295 | zip_path[0] = 0; |
| 296 | } |
| 297 | |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 298 | /* We need to construct a path from the following parts. |
Andrew MacIntyre | 0c83348 | 2003-04-22 03:21:42 +0000 | [diff] [blame] | 299 | * (1) the PYTHONPATH environment variable, if set; |
| 300 | * (2) the zip archive file path; |
| 301 | * (3) the PYTHONPATH config macro, with the leading "." |
| 302 | * of each component replaced with pythonhome, if set; |
| 303 | * (4) the directory containing the executable (argv0_path). |
| 304 | * The length calculation calculates #3 first. |
| 305 | */ |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 306 | |
| 307 | /* Calculate size of return buffer */ |
| 308 | if (pythonhome != NULL) { |
| 309 | char *p; |
| 310 | bufsz = 1; |
| 311 | for (p = PYTHONPATH; *p; p++) { |
| 312 | if (*p == DELIM) |
| 313 | bufsz++; /* number of DELIM plus one */ |
| 314 | } |
| 315 | bufsz *= strlen(pythonhome); |
| 316 | } |
| 317 | else |
| 318 | bufsz = 0; |
| 319 | bufsz += strlen(PYTHONPATH) + 1; |
| 320 | bufsz += strlen(argv0_path) + 1; |
Andrew MacIntyre | 214d39a | 2003-01-02 12:41:58 +0000 | [diff] [blame] | 321 | bufsz += strlen(zip_path) + 1; |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 322 | if (envpath != NULL) |
| 323 | bufsz += strlen(envpath) + 1; |
| 324 | |
| 325 | module_search_path = buf = malloc(bufsz); |
| 326 | if (buf == NULL) { |
| 327 | /* We can't exit, so print a warning and limp along */ |
| 328 | fprintf(stderr, "Can't malloc dynamic PYTHONPATH.\n"); |
| 329 | if (envpath) { |
| 330 | fprintf(stderr, "Using environment $PYTHONPATH.\n"); |
| 331 | module_search_path = envpath; |
| 332 | } |
| 333 | else { |
| 334 | fprintf(stderr, "Using default static path.\n"); |
| 335 | module_search_path = PYTHONPATH; |
| 336 | } |
| 337 | return; |
| 338 | } |
| 339 | |
| 340 | if (envpath) { |
| 341 | strcpy(buf, envpath); |
| 342 | buf = strchr(buf, '\0'); |
| 343 | *buf++ = DELIM; |
| 344 | } |
Andrew MacIntyre | 214d39a | 2003-01-02 12:41:58 +0000 | [diff] [blame] | 345 | if (zip_path[0]) { |
| 346 | strcpy(buf, zip_path); |
| 347 | buf = strchr(buf, '\0'); |
| 348 | *buf++ = DELIM; |
| 349 | } |
Andrew MacIntyre | 41d97d6 | 2002-02-17 05:23:30 +0000 | [diff] [blame] | 350 | |
| 351 | if (pythonhome == NULL) { |
| 352 | strcpy(buf, PYTHONPATH); |
| 353 | buf = strchr(buf, '\0'); |
| 354 | } |
| 355 | else { |
| 356 | char *p = PYTHONPATH; |
| 357 | char *q; |
| 358 | size_t n; |
| 359 | for (;;) { |
| 360 | q = strchr(p, DELIM); |
| 361 | if (q == NULL) |
| 362 | n = strlen(p); |
| 363 | else |
| 364 | n = q-p; |
| 365 | if (p[0] == '.' && is_sep(p[1])) { |
| 366 | strcpy(buf, pythonhome); |
| 367 | buf = strchr(buf, '\0'); |
| 368 | p++; |
| 369 | n--; |
| 370 | } |
| 371 | strncpy(buf, p, n); |
| 372 | buf += n; |
| 373 | if (q == NULL) |
| 374 | break; |
| 375 | *buf++ = DELIM; |
| 376 | p = q+1; |
| 377 | } |
| 378 | } |
| 379 | if (argv0_path) { |
| 380 | *buf++ = DELIM; |
| 381 | strcpy(buf, argv0_path); |
| 382 | buf = strchr(buf, '\0'); |
| 383 | } |
| 384 | *buf = '\0'; |
| 385 | } |
| 386 | |
| 387 | |
| 388 | /* External interface */ |
| 389 | |
| 390 | char * |
| 391 | Py_GetPath(void) |
| 392 | { |
| 393 | if (!module_search_path) |
| 394 | calculate_path(); |
| 395 | return module_search_path; |
| 396 | } |
| 397 | |
| 398 | char * |
| 399 | Py_GetPrefix(void) |
| 400 | { |
| 401 | if (!module_search_path) |
| 402 | calculate_path(); |
| 403 | return prefix; |
| 404 | } |
| 405 | |
| 406 | char * |
| 407 | Py_GetExecPrefix(void) |
| 408 | { |
| 409 | return Py_GetPrefix(); |
| 410 | } |
| 411 | |
| 412 | char * |
| 413 | Py_GetProgramFullPath(void) |
| 414 | { |
| 415 | if (!module_search_path) |
| 416 | calculate_path(); |
| 417 | return progpath; |
| 418 | } |