diff options
author | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
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committer | tcsullivan <tullivan99@gmail.com> | 2018-11-17 13:02:57 -0500 |
commit | c6ef89664b8c0d7aa85bddd5c7014aa6df82cbe7 (patch) | |
tree | d1f9d09412a46bdf4344fe30392455070a72993d /src/pdclib/functions/stdlib/bsearch.c | |
parent | db38c4b9dac461de0ed75bf6d079dacba1b31bc9 (diff) |
added pdclib, removed sash
Diffstat (limited to 'src/pdclib/functions/stdlib/bsearch.c')
-rw-r--r-- | src/pdclib/functions/stdlib/bsearch.c | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/src/pdclib/functions/stdlib/bsearch.c b/src/pdclib/functions/stdlib/bsearch.c new file mode 100644 index 0000000..211c55c --- /dev/null +++ b/src/pdclib/functions/stdlib/bsearch.c @@ -0,0 +1,61 @@ +/* bsearch( const void *, const void *, size_t, size_t, int(*)( const void *, const void * ) ) + + This file is part of the Public Domain C Library (PDCLib). + Permission is granted to use, modify, and / or redistribute at will. +*/ + +#include <stdlib.h> + +#ifndef REGTEST + +void * bsearch( const void * key, const void * base, size_t nmemb, size_t size, int (*compar)( const void *, const void * ) ) +{ + const void * pivot; + int rc; + size_t corr; + while ( nmemb ) + { + /* algorithm needs -1 correction if remaining elements are an even number. */ + corr = nmemb % 2; + nmemb /= 2; + pivot = (const char *)base + (nmemb * size); + rc = compar( key, pivot ); + if ( rc > 0 ) + { + base = (const char *)pivot + size; + /* applying correction */ + nmemb -= ( 1 - corr ); + } + else if ( rc == 0 ) + { + return (void *)pivot; + } + } + return NULL; +} + +#endif + +#ifdef TEST + +#include "_PDCLIB_test.h" + +static int compare( const void * left, const void * right ) +{ + return *( (unsigned char *)left ) - *( (unsigned char *)right ); +} + +int main( void ) +{ + TESTCASE( bsearch( "e", abcde, 4, 1, compare ) == NULL ); + TESTCASE( bsearch( "e", abcde, 5, 1, compare ) == &abcde[4] ); + TESTCASE( bsearch( "a", abcde + 1, 4, 1, compare ) == NULL ); + TESTCASE( bsearch( "0", abcde, 1, 1, compare ) == NULL ); + TESTCASE( bsearch( "a", abcde, 1, 1, compare ) == &abcde[0] ); + TESTCASE( bsearch( "a", abcde, 0, 1, compare ) == NULL ); + TESTCASE( bsearch( "e", abcde, 3, 2, compare ) == &abcde[4] ); + TESTCASE( bsearch( "b", abcde, 3, 2, compare ) == NULL ); + return TEST_RESULTS; +} + +#endif |