lib: add strtosize() function

This function

  int strtosize(const char *str, uintmax_t *res)

supports {K,M,G,T,E,P}iB and {K,M,G,T,E,P}B suffixes.

Signed-off-by: Karel Zak <kzak@redhat.com>

7 files changed, 235 insertions, 1 deletions

diff --git a/include/Makefile.am b/include/Makefile.am
index ccae85d7c..65e447d51 100644
--- a/include/Makefile.am
+++ b/include/Makefile.am
@@ -22,4 +22,5 @@ dist_noinst_HEADERS = \
 	widechar.h \
 	crc32.h \
 	mangle.h \
+	strtosize.h \
 	xstrncpy.h
diff --git a/include/strtosize.h b/include/strtosize.h
new file mode 100644
index 000000000..c789df93d
--- /dev/null
+++ b/include/strtosize.h
@@ -0,0 +1,8 @@
+#ifndef UTIL_LINUX_STRTOSIZE
+#define UTIL_LINUX_STRTOSIZE
+
+#include <inttypes.h>
+
+extern int strtosize(const char *str, uintmax_t *res);
+
+#endif /* UTIL_LINUX_STRING_TO_NUMBE */
diff --git a/lib/Makefile.am b/lib/Makefile.am
index 0fddfb5ed..0f008b302 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -2,12 +2,14 @@ include $(top_srcdir)/config/include-Makefile.am
 
 AM_CPPFLAGS += -DTEST_PROGRAM
 
-noinst_PROGRAMS = test_blkdev test_ismounted test_wholedisk test_mangle
+noinst_PROGRAMS = test_blkdev test_ismounted test_wholedisk test_mangle \
+		  test_strtosize
 
 test_blkdev_SOURCES = blkdev.c
 test_ismounted_SOURCES = ismounted.c
 test_wholedisk_SOURCES = wholedisk.c
 test_mangle_SOURCES = mangle.c
+test_strtosize_SOURCES = strtosize.c
 
 if LINUX
 test_blkdev_SOURCES += linux_version.c
diff --git a/lib/strtosize.c b/lib/strtosize.c
new file mode 100644
index 000000000..068c5429a
--- /dev/null
+++ b/lib/strtosize.c
@@ -0,0 +1,148 @@
+/*
+ * strtosize() - convert string to size (uintmax_t).
+ *
+ * Supported suffixes:
+ *
+ * XiB or X for 2^N
+ *     where X = {K,M,G,T,P,E,Y,Z}
+ *        or X = {k,m,g,t,p,e}  (undocumented for backward compatibility only)
+ * for example:
+ *		10KiB	= 10240
+ *		10K	= 10240
+ *
+ * XB for 10^N
+ *     where X = {K,M,G,T,P,E,Y,Z}
+ * for example:
+ *		10KB	= 10000
+ *
+ * Note that the function does not accept numbers with '-' (negative sign)
+ * prefix.
+ *
+ * Returns 0 on success, -1 in case of error, -2 in case of overflow.
+ *
+ * Copyright (C) 2010 Karel Zak <kzak@redhat.com>
+ */
+#include <stdio.h>
+#include <inttypes.h>
+#include <ctype.h>
+#include <errno.h>
+
+static int do_scale_by_power (uintmax_t *x, int base, int power)
+{
+	while (power--) {
+		if (UINTMAX_MAX / base < *x)
+			return -2;
+		*x *= base;
+	}
+	return 0;
+}
+
+int strtosize(const char *str, uintmax_t *res)
+{
+	char *p;
+	uintmax_t x;
+	int base = 1024, rc = 0;
+
+	*res = 0;
+
+	if (!str || !*str)
+		goto err;
+
+	/* Only positive numbers are acceptable
+	 *
+	 * Note that this check is not perfect, it would be better to
+	 * use lconv->negative_sign. But coreutils use the same solution,
+	 * so it's probably good enough...
+	 */
+	p = (char *) str;
+	while (isspace((unsigned char) *p))
+		p++;
+	if (*p == '-')
+		goto err;
+	p = NULL;
+
+	errno = 0;
+	x = strtoumax(str, &p, 0);
+
+	if (p == str ||
+	    (errno != 0 && (x == UINTMAX_MAX || x == 0)))
+		goto err;
+
+	if (!p || !*p)
+		goto done;			/* without suffix */
+
+	/*
+	 * Check size suffixes
+	 */
+	if (*(p + 1) == 'i' && *(p + 2) == 'B' && !*(p + 3))
+		base = 1024;			/* XiB, 2^N */
+	else if (*(p + 1) == 'B' && !*(p + 2))
+		base = 1000;			/* XB, 10^N */
+	else if (*(p + 1))
+		goto err;			/* unexpected suffix */
+
+	switch(*p) {
+	case 'K':
+	case 'k':
+		rc = do_scale_by_power(&x, base, 1);
+		break;
+	case 'M':
+	case 'm':
+		rc = do_scale_by_power(&x, base, 2);
+		break;
+	case 'G':
+	case 'g':
+		rc = do_scale_by_power(&x, base, 3);
+		break;
+	case 'T':
+	case 't':
+		rc = do_scale_by_power(&x, base, 4);
+		break;
+	case 'P':
+	case 'p':
+		rc = do_scale_by_power(&x, base, 5);
+		break;
+	case 'E':
+	case 'e':
+		rc = do_scale_by_power(&x, base, 6);
+		break;
+	case 'Z':
+		rc = do_scale_by_power(&x, base, 7);
+		break;
+	case 'Y':
+		rc = do_scale_by_power(&x, base, 8);
+		break;
+	default:
+		goto err;
+	}
+
+done:
+	*res = x;
+	return rc;
+err:
+	return -1;
+}
+
+#ifdef TEST_PROGRAM
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <err.h>
+
+int main(int argc, char *argv[])
+{
+	uintmax_t size = 0;
+
+	if (argc < 2) {
+		fprintf(stderr, "usage: %s <number>[suffix]\n",	argv[0]);
+		exit(EXIT_FAILURE);
+	}
+
+	if (strtosize(argv[1], &size))
+		errx(EXIT_FAILURE, "invalid size '%s' value", argv[1]);
+
+	printf("%25s : %20ju\n", argv[1], size);
+	return EXIT_FAILURE;
+}
+#endif /* TEST_PROGRAM */
+
diff --git a/tests/commands.sh.in b/tests/commands.sh.in
index 8399738c8..f52a68687 100644
--- a/tests/commands.sh.in
+++ b/tests/commands.sh.in
@@ -10,6 +10,7 @@ TS_HELPER_BYTESWAP="$TS_TOPDIR/helpers/test_byteswap"
 TS_HELPER_MD5="$TS_TOPDIR/helpers/test_md5"
 
 TS_HELPER_ISMOUNTED="$TOPDIR/lib/test_ismounted"
+TS_HELPER_STRTOSIZE="$TOPDIR/lib/test_strtosize"
 
 # TODO: use partx
 TS_HELPER_PARTITIONS="$TOPDIR/shlibs/blkid/samples/partitions"
diff --git a/tests/expected/misc/strtosize b/tests/expected/misc/strtosize
new file mode 100644
index 000000000..b7cb24617
--- /dev/null
+++ b/tests/expected/misc/strtosize
@@ -0,0 +1,23 @@
+test_strtosize: invalid size '-1' value
+                        0 :                    0
+                        1 :                    1
+                      123 :                  123
+     18446744073709551615 : 18446744073709551615
+                       1K :                 1024
+                     1KiB :                 1024
+                       1M :              1048576
+                     1MiB :              1048576
+                       1G :           1073741824
+                     1GiB :           1073741824
+                       1T :        1099511627776
+                     1TiB :        1099511627776
+                       1P :     1125899906842624
+                     1PiB :     1125899906842624
+                       1E :  1152921504606846976
+                     1EiB :  1152921504606846976
+                      1KB :                 1000
+                      1MB :              1000000
+                      1GB :           1000000000
+                      1TB :        1000000000000
+                      1PB :     1000000000000000
+                      1EB :  1000000000000000000
diff --git a/tests/ts/misc/strtosize b/tests/ts/misc/strtosize
new file mode 100755
index 000000000..4668823c6
--- /dev/null
+++ b/tests/ts/misc/strtosize
@@ -0,0 +1,51 @@
+#!/bin/bash
+
+#
+# Copyright (C) 2010 Karel Zak <kzak@redhat.com>
+#
+# This file is part of util-linux-ng.
+#
+# This file 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 2 of the License, or
+# (at your option) any later version.
+#
+# This file 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.
+#
+TS_TOPDIR="$(dirname $0)/../.."
+TS_DESC="strtosize"
+
+. $TS_TOPDIR/functions.sh
+ts_init "$*"
+
+$TS_HELPER_STRTOSIZE -1 >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 0 >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1 >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 123 >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 18446744073709551615 >> $TS_OUTPUT 2>&1
+
+$TS_HELPER_STRTOSIZE 1K >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1KiB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1M >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1MiB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1G >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1GiB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1T >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1TiB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1P >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1PiB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1E >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1EiB >> $TS_OUTPUT 2>&1
+
+$TS_HELPER_STRTOSIZE 1KB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1MB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1GB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1TB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1PB >> $TS_OUTPUT 2>&1
+$TS_HELPER_STRTOSIZE 1EB >> $TS_OUTPUT 2>&1
+
+ts_finalize
+