/* kdefault.c: Expand extra colons. (This is not named default.c because then the OSF/1 make tries to make a program `default' from it, since we have a target `default'; and OSF/1 make doesn't understand .PHONY.) Copyright (C) 1993, 94, 96 Karl Berry. This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include #include #include /* Check for leading colon first, then trailing, then doubled, since that is fastest. Usually it will be leading or trailing. */ string kpse_expand_default P2C(const_string, path, const_string, fallback) { unsigned path_length; string expansion; /* The default path better not be null. */ assert (fallback); if (path == NULL) expansion = (string) fallback; /* Solitary or leading :? */ else if (IS_ENV_SEP (*path)) { expansion = path[1] == 0 ? (string) fallback : concat (fallback, path); } /* Sorry about the assignment in the middle of the expression, but conventions were made to be flouted and all that. I don't see the point of calling strlen twice or complicating the logic just to avoid the assignment (especially now that I've pointed it out at such great length). */ else if (path[(path_length = strlen (path)) - 1] == ENV_SEP) expansion = concat (path, fallback); /* OK, not leading or trailing. Check for doubled. */ else { const_string loc; /* What we'll return if we find none. */ expansion = (string) path; for (loc = path; *loc && expansion == path; loc++) { if (IS_ENV_SEP (loc[0]) && IS_ENV_SEP (loc[1])) { /* We have a doubled colon. */ expansion = xmalloc (path_length + strlen (fallback) + 1); /* Copy stuff up to and including the first colon. */ strncpy (expansion, path, loc - path + 1); expansion[loc - path + 1] = 0; /* Copy in FALLBACK, and then the rest of PATH. */ strcat (expansion, fallback); strcat (expansion, loc + 1); } } } return expansion; } #ifdef TEST void test_expand_default (const_string path, const_string def) { string answer; printf ("Expansion of `%s':\t", path ? path : "(nil)"); answer = kpse_expand_default (path, def); puts (answer); } int main () { string default_path = "default"; test_expand_default (NULL, default_path); test_expand_default ("", default_path); test_expand_default ("none", default_path); test_expand_default (ENV_SEP_STRING, default_path); test_expand_default (ENV_SEP_STRING "first", default_path); test_expand_default ("last" ENV_SEP_STRING, default_path); test_expand_default ("middle" ENV_SEP_STRING ENV_SEP_STRING "elddim", default_path); return 0; } #endif /* TEST */ /* Local variables: standalone-compile-command: "gcc -g -I. -I.. -DTEST default.c kpathsea.a" End: */