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Diffstat (limited to 'src/pcheck.cc')
-rw-r--r-- | src/pcheck.cc | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/src/pcheck.cc b/src/pcheck.cc new file mode 100644 index 00000000..d5401f7d --- /dev/null +++ b/src/pcheck.cc @@ -0,0 +1,154 @@ +/* + * Copyright 2006-2012 Adrian Thurston <thurston@complang.org> + */ + +/* This file is part of Colm. + * + * Colm is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * Colm 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 General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with Colm; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#include "pcheck.h" +#include <assert.h> + +/* Construct a new parameter checker with for paramSpec. */ +ParamCheck::ParamCheck( const char *paramSpec, int argc, const char **argv ) +: + state(noparam), + argOffset(0), + curArg(0), + iCurArg(1), + paramSpec(paramSpec), + argc(argc), + argv(argv) +{ +} + +/* Check a single option. Returns the index of the next parameter. Sets p to + * the arg character if valid, 0 otherwise. Sets parg to the parameter arg if + * there is one, NULL otherwise. */ +bool ParamCheck::check() +{ + bool requiresParam; + + if ( iCurArg >= argc ) { /* Off the end of the arg list. */ + state = noparam; + return false; + } + + if ( argOffset != 0 && *argOffset == 0 ) { + /* We are at the end of an arg string. */ + iCurArg += 1; + if ( iCurArg >= argc ) { + state = noparam; + return false; + } + argOffset = 0; + } + + if ( argOffset == 0 ) { + /* Set the current arg. */ + curArg = argv[iCurArg]; + + /* We are at the beginning of an arg string. */ + if ( argv[iCurArg] == 0 || /* Argv[iCurArg] is null. */ + argv[iCurArg][0] != '-' || /* Not a param. */ + argv[iCurArg][1] == 0 ) { /* Only a dash. */ + parameter = 0; + parameterArg = 0; + + iCurArg += 1; + state = noparam; + return true; + } + argOffset = argv[iCurArg] + 1; + } + + /* Get the arg char. */ + char argChar = *argOffset; + + /* Loop over all the parms and look for a match. */ + const char *pSpec = paramSpec; + while ( *pSpec != 0 ) { + char pSpecChar = *pSpec; + + /* If there is a ':' following the char then + * it requires a parm. If a parm is required + * then move ahead two in the parmspec. Otherwise + * move ahead one in the parm spec. */ + if ( pSpec[1] == ':' ) { + requiresParam = true; + pSpec += 2; + } + else { + requiresParam = false; + pSpec += 1; + } + + /* Do we have a match. */ + if ( argChar == pSpecChar ) { + if ( requiresParam ) { + if ( argOffset[1] == 0 ) { + /* The param must follow. */ + if ( iCurArg + 1 == argc ) { + /* We are the last arg so there + * cannot be a parameter to it. */ + parameter = argChar; + parameterArg = 0; + iCurArg += 1; + argOffset = 0; + state = invalid; + return true; + } + else { + /* the parameter to the arg is the next arg. */ + parameter = pSpecChar; + parameterArg = argv[iCurArg + 1]; + iCurArg += 2; + argOffset = 0; + state = match; + return true; + } + } + else { + /* The param for the arg is built in. */ + parameter = pSpecChar; + parameterArg = argOffset + 1; + iCurArg += 1; + argOffset = 0; + state = match; + return true; + } + } + else { + /* Good, we matched the parm and no + * arg is required. */ + parameter = pSpecChar; + parameterArg = 0; + argOffset += 1; + state = match; + return true; + } + } + } + + /* We did not find a match. Bad Argument. */ + parameter = argChar; + parameterArg = 0; + argOffset += 1; + state = invalid; + return true; +} + + |