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authortcsullivan <tullivan99@gmail.com>2018-11-17 13:02:57 -0500
committertcsullivan <tullivan99@gmail.com>2018-11-17 13:02:57 -0500
commitc6ef89664b8c0d7aa85bddd5c7014aa6df82cbe7 (patch)
treed1f9d09412a46bdf4344fe30392455070a72993d /src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c
parentdb38c4b9dac461de0ed75bf6d079dacba1b31bc9 (diff)
added pdclib, removed sash
Diffstat (limited to 'src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c')
-rw-r--r--src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c94
1 files changed, 94 insertions, 0 deletions
diff --git a/src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c b/src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c
new file mode 100644
index 0000000..6e16b35
--- /dev/null
+++ b/src/pdclib/functions/_PDCLIB/_PDCLIB_strtox_prelim.c
@@ -0,0 +1,94 @@
+/* _PDCLIB_strtox_prelim( const char *, char *, int * )
+
+ This file is part of the Public Domain C Library (PDCLib).
+ Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <ctype.h>
+#include <stddef.h>
+#include <string.h>
+
+#ifndef REGTEST
+
+const char * _PDCLIB_strtox_prelim( const char * p, char * sign, int * base )
+{
+ /* skipping leading whitespace */
+ while ( isspace( *p ) ) ++p;
+ /* determining / skipping sign */
+ if ( *p != '+' && *p != '-' ) *sign = '+';
+ else *sign = *(p++);
+ /* determining base */
+ if ( *p == '0' )
+ {
+ ++p;
+ if ( ( *base == 0 || *base == 16 ) && ( *p == 'x' || *p == 'X' ) )
+ {
+ *base = 16;
+ ++p;
+ /* catching a border case here: "0x" followed by a non-digit should
+ be parsed as the unprefixed zero.
+ We have to "rewind" the parsing; having the base set to 16 if it
+ was zero previously does not hurt, as the result is zero anyway.
+ */
+ if ( memchr( _PDCLIB_digits, tolower(*p), *base ) == NULL )
+ {
+ p -= 2;
+ }
+ }
+ else if ( *base == 0 )
+ {
+ *base = 8;
+ }
+ else
+ {
+ --p;
+ }
+ }
+ else if ( ! *base )
+ {
+ *base = 10;
+ }
+ return ( ( *base >= 2 ) && ( *base <= 36 ) ) ? p : NULL;
+}
+
+#endif
+
+#ifdef TEST
+
+#include "_PDCLIB_test.h"
+
+int main( void )
+{
+#ifndef REGTEST
+ int base = 0;
+ char sign = '\0';
+ char test1[] = " 123";
+ char test2[] = "\t+0123";
+ char test3[] = "\v-0x123";
+ TESTCASE( _PDCLIB_strtox_prelim( test1, &sign, &base ) == &test1[2] );
+ TESTCASE( sign == '+' );
+ TESTCASE( base == 10 );
+ base = 0;
+ sign = '\0';
+ TESTCASE( _PDCLIB_strtox_prelim( test2, &sign, &base ) == &test2[3] );
+ TESTCASE( sign == '+' );
+ TESTCASE( base == 8 );
+ base = 0;
+ sign = '\0';
+ TESTCASE( _PDCLIB_strtox_prelim( test3, &sign, &base ) == &test3[4] );
+ TESTCASE( sign == '-' );
+ TESTCASE( base == 16 );
+ base = 10;
+ sign = '\0';
+ TESTCASE( _PDCLIB_strtox_prelim( test3, &sign, &base ) == &test3[2] );
+ TESTCASE( sign == '-' );
+ TESTCASE( base == 10 );
+ base = 1;
+ TESTCASE( _PDCLIB_strtox_prelim( test3, &sign, &base ) == NULL );
+ base = 37;
+ TESTCASE( _PDCLIB_strtox_prelim( test3, &sign, &base ) == NULL );
+#endif
+ return TEST_RESULTS;
+}
+
+#endif