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author | al <al@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2004-12-31 11:11:24 +0000 |
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committer | al <al@b3059339-0415-0410-9bf9-f77b7e298cf2> | 2004-12-31 11:11:24 +0000 |
commit | 672dc76569e0ac4cfc9a76fe14d0efa654c70826 (patch) | |
tree | 31b37a1e58d7da013b0741418f14539fd80842b0 /subopt-helper.c | |
parent | fc91fed21ea71c50273c7c09f88e8d634c1e444e (diff) | |
download | mpv-672dc76569e0ac4cfc9a76fe14d0efa654c70826.tar.bz2 mpv-672dc76569e0ac4cfc9a76fe14d0efa654c70826.tar.xz |
suboption parser for vo and ao modules
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@14282 b3059339-0415-0410-9bf9-f77b7e298cf2
Diffstat (limited to 'subopt-helper.c')
-rw-r--r-- | subopt-helper.c | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/subopt-helper.c b/subopt-helper.c new file mode 100644 index 0000000000..7ae5512f3d --- /dev/null +++ b/subopt-helper.c @@ -0,0 +1,256 @@ +/** + * \file subopt-helper.c + * + * \brief Compensates the suboption parsing code duplication a bit. + * + * The routines defined below are there to help you with the + * suboption parsing. Meaning extracting the options and their + * values for you and also outputting generic help message if + * a parse error is encountered. + * + * Most stuff happens in the subopt_parse function: if you call it + * it parses for the passed opts in the passed string. It calls some + * extra functions for explicit argument parsing ( where the option + * itself isn't the argument but a value given after the argument + * delimiter ('='). It also calls your test function if you supplied + * one. + * + */ + +#include "subopt-helper.h" +#include "mp_msg.h" + +#include <stdlib.h> +#include <string.h> +#include <assert.h> + +#ifndef MPDEBUG + #define NDEBUG +#endif + +/* prototypes for argument parsing */ +static char const * parse_int( char const * const str, int * const valp ); +static char const * parse_str( char const * const str, strarg_t * const valp ); + +/** + * \brief Try to parse all options in str and fail if it was not possible. + * + * \param str Pointer to the zero terminated string to be parsed. + * \param opts Pointer to a options array. The array must be terminated + * with an element having set name to NULL in its opt_t structure. + * + * \return The return value is zero if the string could be parsed + * else a non-zero value is returned. + * + */ +int subopt_parse( char const * const str, opt_t * opts ) +{ + int parse_err = 0, idx; + unsigned int parse_pos = 0; + + /* Initialize set member to false. * + * It is set to true if it was found in str */ + for ( idx=0; opts[idx].name; ++idx ) + { + opts[idx].set = 0; + } + + if ( str ) + { + while ( str[parse_pos] && !parse_err ) + { + int next = 0; + + idx = 0; // reset index for the below loop + while ( opts[idx].name ) + { + int opt_len; + int substr_len; + + // get length of the option we test against */ + opt_len = strlen( opts[idx].name ); + + // get length of the current substring of str */ + { + char * delim, * arg_delim; + + /* search nearest delimiter ( option or argument delimiter ) */ + delim = strchr( &str[parse_pos], ':' ); + arg_delim = strchr( &str[parse_pos], '=' ); + + if ( ( delim && arg_delim && delim > arg_delim ) || + delim == NULL ) + { + delim = strchr( &str[parse_pos], '=' ); + } + + substr_len = delim ? // is a delim present + delim - &str[parse_pos] : // yes + strlen( &str[parse_pos] ); // no, end of string + } + + //printf( "substr_len=%d, opt_len=%d\n", substr_len, opt_len ); + + /* Check if the length of the current option matches the * + * length of the option we want to test again. */ + if ( substr_len == opt_len ) +{ + /* check if option was activated/deactivated */ + if( strncmp( &str[parse_pos], opts[idx].name, opt_len ) == 0 ) + { + /* option was found */ + opts[idx].set = 1; next = 1; + + assert( opts[idx].valp && "Need a pointer to store the arg!" ); + + /* type specific code */ + if ( opts[idx].type == OPT_ARG_BOOL ) + { + /* Handle OPT_ARG_BOOL seperately so * + * the others can share code. */ + + /* set option to true */ + *((int *)(opts[idx].valp)) = 1; + + /* increment position */ + parse_pos += opt_len; + } + else + { + /* Type is not OPT_ARG_BOOL, means we have to parse * + * for the arg delimiter character and eventually * + * call a test function. */ + char const * last; + + /* increment position to check for arg */ + parse_pos += opt_len; + + if ( str[parse_pos] != '=' ) + { + parse_err = 1; break; + } + + /* '=' char was there, so let's move after it */ + ++parse_pos; + + switch ( opts[idx].type ) + { + case OPT_ARG_INT: + last = parse_int( &str[parse_pos], + (int *)opts[idx].valp ); + + break; + case OPT_ARG_STR: + last = parse_str( &str[parse_pos], + (strarg_t *)opts[idx].valp ); + break; + default: + assert( 0 && "Arg type of suboption doesn't exist!" ); + last = NULL; // break parsing! + } + + /* was the conversion succesful? */ + if ( !last ) + { + parse_err = 1; break; + } + + /* make test if supplied */ + if ( opts[idx].test && !opts[idx].test( opts[idx].valp ) ) + { + parse_err = 1; break; + } + + /* we succeded, set position */ + parse_pos = last - str; + } + } +} +else if ( substr_len == opt_len+2 ) +{ + if ( opts[idx].type == OPT_ARG_BOOL && // check for no<opt> + strncmp( &str[parse_pos], "no", 2 ) == 0 && + strncmp( &str[parse_pos+2], opts[idx].name, opt_len ) == 0 ) + { + /* option was found but negated */ + opts[idx].set = 1; next = 1; + + /* set arg to false */ + *((int *)(opts[idx].valp)) = 0; + + /* increment position */ + parse_pos += opt_len+2; + } +} + + ++idx; // test against next option + + /* break out of the loop, if this subopt is processed */ + if ( next ) { break; } + } + + /* if we had a valid suboption the current pos should * + * equal the delimiter char, which should be ':' for * + * suboptions. */ + if ( !parse_err && str[parse_pos] == ':' ) { ++parse_pos; } + else if ( str[parse_pos] ) { parse_err = 1; } + } + } + + /* if an error was encountered */ + if (parse_err) + { + unsigned int i; + mp_msg( MSGT_VO, MSGL_FATAL, "Could not parse arguments at the position indicated below:\n%s\n", str ); + for ( i = 0; i < parse_pos; ++i ) + { + mp_msg(MSGT_VO, MSGL_FATAL, " "); + } + mp_msg(MSGT_VO, MSGL_FATAL, "^\n"); + + return -1; + } + + /* we could parse everything */ + return 0; +} + +static char const * parse_int( char const * const str, int * const valp ) +{ + char * endp; + + assert( str && "parse_int(): str == NULL" ); + + *valp = (int)strtol( str, &endp, 0 ); + + /* nothing was converted */ + if ( str == endp ) { return NULL; } + + return endp; +} + +static char const * parse_str( char const * const str, strarg_t * const valp ) +{ + char const * match = strchr( str, ':' ); + + if ( !match ) + { + if ( str[1] != '\0' ) + { + int len = strlen( &str[1] ); + match = str + 1 + len; + } + else + { + return NULL; + } + } + + valp->len = match - str; + valp->str = str; + + /* if the length is zero, indicate error */ + if ( valp->len == 0 ) { return NULL; } + + return match; +} |