Release calc version 2.10.2t30

math_error.c

@@ -0,0 +1,104 @@
+/*
+ * math_error - a simple libcalc math error routine
+ */
+/*
+ * Copyright (c) 1995 by Landon Curt Noll.  All Rights Reserved.
+ *
+ * Permission to use, copy, modify, and distribute this software and
+ * its documentation for any purpose and without fee is hereby granted,
+ * provided that the above copyright, this permission notice and text
+ * this comment, and the disclaimer below appear in all of the following:
+ *
+ *	supporting documentation
+ *	source copies
+ *	source works derived from this source
+ *	binaries derived from this source or from derived source
+ *
+ * LANDON CURT NOLL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO
+ * EVENT SHALL LANDON CURT NOLL BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
+ * USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+ * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ *
+ * chongo was here	/\../\
+ */
+/*
+ * Your program MUST provide a function called math_error.  This is called
+ * by the math routines on an error condition, such as malloc failures or a
+ * division by zero.  The routine is called in the manner of printf, with a
+ * format string and optional arguments.
+ *
+ * By default, this routine simply prints a message to stderr and then exits.
+ *
+ * If one sets up calc_jmp_buf, and then sets calc_jmp to non-zero then
+ * this routine will longjmp back (with the value of calc_jmp) instead.
+ * In addition, the last calc error message will be found in calc_error;
+ * this error is not printed to sttderr.
+ *
+ * For example:
+ *
+ *	#include <setjmp.h>
+ *
+ *	extern jmp_buf calc_jmp_buf;
+ *	extern int calc_jmp;
+ *	extern char *calc_error;
+ *	int error;
+ *
+ *	...
+ *
+ *	if ((error = setjmp(calc_jmp_buf)) != 0) {
+ *		printf("Ouch: %s\n", calc_error);
+ *	}
+ *	calc_jmp = 1;
+ */
+
+#include <stdio.h>
+#include <setjmp.h>
+#include "args.h"
+#include "calc.h"
+
+/*
+ * error jump point we will longjmp to this jmp_buf if calc_jmp is non-zero
+ */
+jmp_buf calc_jmp_buf;
+int calc_jmp = 0;		/* non-zero => use calc_jmp_buf */
+char calc_error[MAXERROR+1];	/* last calc error message */
+
+
+/*
+ * math_error - print a math error and exit
+ */
+void
+math_error(char *fmt, ...)
+{
+	va_list ap;
+
+	/*
+	 * format the error
+	 */
+#ifdef VARARGS
+	va_start(ap);
+#else
+	va_start(ap, fmt);
+#endif
+	vsprintf(calc_error, fmt, ap);
+	va_end(ap);
+
+	/*
+	 * if we should longjmp, so do
+	 */
+	if (calc_jmp != 0) {
+		longjmp(calc_jmp_buf, calc_jmp);
+	}
+
+	/*
+	 * print error message and edit
+	 */
+	(void) fflush(stdout);
+	(void) fflush(stderr);
+	fprintf(stderr, "%s\n", calc_error);
+	fputc('\n', stderr);
+	exit(1);
+}