Helper functions for strto...() functions.

[pdclib] / functions / _PDCLIB / strtox_main.c

diff --git a/functions/_PDCLIB/strtox_main.c b/functions/_PDCLIB/strtox_main.c
new file mode 100644 (file)
index 0000000..6ab56cd
--- /dev/null
+++ b/functions/_PDCLIB/strtox_main.c
@@ -0,0 +1,79 @@
+/* $Id$ */
+
+/* Release $Name$ */
+
+/* _PDCLIB_strtox_main( const char * *, int, _PDCLIB_uintmax_t, _PDCLIB_uintmax_t, int )
+
+   This file is part of the Public Domain C Library (PDCLib).
+   Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <_PDCLIB_int.h>
+#include <ctype.h>
+#include <errno.h>
+#include <string.h>
+
+_PDCLIB_uintmax_t _PDCLIB_strtox_main( const char ** p, int base, _PDCLIB_uintmax_t error, _PDCLIB_uintmax_t limval, int limdigit )
+{
+    _PDCLIB_uintmax_t rc = 0;
+    int digit = -1;
+    const char * x;
+    while ( ( x = memchr( _PDCLIB_digits, toupper(**p), base ) ) != NULL )
+    {
+        digit = x - _PDCLIB_digits;
+        if ( ( rc < limval ) || ( ( rc == limval ) && ( digit <= limdigit ) ) )
+        {
+            rc = rc * base + ( x - _PDCLIB_digits );
+            ++(*p);
+        }
+        else
+        {
+            errno = ERANGE;
+            /* TODO: Only if endptr != NULL */
+            while ( memchr( _PDCLIB_digits, **p, base ) != NULL ) ++(*p);
+            return error;
+        }
+    }
+    if ( digit == -1 )
+    {
+        *p = NULL;
+        return 0;
+    }
+    return rc;
+}
+
+#ifdef TEST
+#include <_PDCLIB_test.h>
+#include <errno.h>
+
+int main()
+{
+    const char * p;
+    char test[] = "123_";
+    char fail[] = "xxx";
+    BEGIN_TESTS;
+    /* basic functionality */
+    p = test;
+    errno = 0;
+    TESTCASE( _PDCLIB_strtox_main( &p, 10, 999, 12, 3 ) == 123 );
+    TESTCASE( errno == 0 );
+    TESTCASE( p == &test[3] );
+    /* proper functioning to smaller base */
+    p = test;
+    TESTCASE( _PDCLIB_strtox_main( &p, 8, 999, 12, 3 ) == 0123 );
+    TESTCASE( errno == 0 );
+    TESTCASE( p == &test[3] );
+    /* overflowing subject sequence must still return proper endptr */
+    p = test;
+    TESTCASE( _PDCLIB_strtox_main( &p, 4, 999, 1, 2 ) == 999 );
+    TESTCASE( errno == ERANGE );
+    TESTCASE( p == &test[3] );
+    /* testing conversion failure */
+    errno = 0;
+    p = fail;
+    TESTCASE( _PDCLIB_strtox_main( &p, 10, 999, 99, 8 ) == 0 );
+    TESTCASE( p == NULL );
+    return TEST_RESULTS;
+}
+
+#endif