summaryrefslogtreecommitdiffstats
path: root/lib/sh/uconvert.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/sh/uconvert.c')
-rw-r--r--lib/sh/uconvert.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/lib/sh/uconvert.c b/lib/sh/uconvert.c
new file mode 100644
index 0000000..457552e
--- /dev/null
+++ b/lib/sh/uconvert.c
@@ -0,0 +1,124 @@
+/* uconvert - convert string representations of decimal numbers into whole
+ number/fractional value pairs. */
+
+/* Copyright (C) 2008,2009,2020 Free Software Foundation, Inc.
+
+ This file is part of GNU Bash, the Bourne Again SHell.
+
+ Bash is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Bash is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Bash. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "config.h"
+
+#include "bashtypes.h"
+
+#include "posixtime.h"
+
+#if defined (HAVE_UNISTD_H)
+#include <unistd.h>
+#endif
+
+#include <stdio.h>
+#include "chartypes.h"
+
+#include "shell.h"
+#include "builtins.h"
+
+#define DECIMAL '.' /* XXX - should use locale */
+
+#define RETURN(x) \
+do { \
+ if (ip) *ip = ipart * mult; \
+ if (up) *up = upart; \
+ if (ep) *ep = p; \
+ return (x); \
+} while (0)
+
+/*
+ * An incredibly simplistic floating point converter.
+ */
+static int multiplier[7] = { 1, 100000, 10000, 1000, 100, 10, 1 };
+
+/* Take a decimal number int-part[.[micro-part]] and convert it to the whole
+ and fractional portions. The fractional portion is returned in
+ millionths (micro); callers are responsible for multiplying appropriately.
+ EP, if non-null, gets the address of the character where conversion stops.
+ Return 1 if value converted; 0 if invalid integer for either whole or
+ fractional parts. */
+int
+uconvert(s, ip, up, ep)
+ char *s;
+ long *ip, *up;
+ char **ep;
+{
+ int n, mult;
+ long ipart, upart;
+ char *p;
+
+ ipart = upart = 0;
+ mult = 1;
+
+ if (s && (*s == '-' || *s == '+'))
+ {
+ mult = (*s == '-') ? -1 : 1;
+ p = s + 1;
+ }
+ else
+ p = s;
+
+ for ( ; p && *p; p++)
+ {
+ if (*p == DECIMAL) /* decimal point */
+ break;
+ if (DIGIT(*p) == 0)
+ RETURN(0);
+ ipart = (ipart * 10) + (*p - '0');
+ }
+
+ if (p == 0 || *p == 0) /* callers ensure p can never be 0; this is to shut up clang */
+ RETURN(1);
+
+ if (*p == DECIMAL)
+ p++;
+
+ /* Look for up to six digits past a decimal point. */
+ for (n = 0; n < 6 && p[n]; n++)
+ {
+ if (DIGIT(p[n]) == 0)
+ {
+ if (ep)
+ {
+ upart *= multiplier[n];
+ p += n; /* To set EP */
+ }
+ RETURN(0);
+ }
+ upart = (upart * 10) + (p[n] - '0');
+ }
+
+ /* Now convert to millionths */
+ upart *= multiplier[n];
+
+ if (n == 6 && p[6] >= '5' && p[6] <= '9')
+ upart++; /* round up 1 */
+
+ if (ep)
+ {
+ p += n;
+ while (DIGIT(*p))
+ p++;
+ }
+
+ RETURN(1);
+}