utils-std

commit: a684ae14e6f69ad53bd11f5a4ff84a816bccf047
parent 615c8fdb57fba2630113e3c126af4c7996fec356
Author: Haelwenn (lanodan) Monnier <contact@hacktivis.me>
Date:   Thu, 14 Mar 2024 19:16:42 +0100

cmd/seq: split absolute function to lib/absu.h

Diffstat:
M
Makefile
4
++++
M
cmd/seq.c
25
+++++++------------------
A
lib/absu.h
36
++++++++++++++++++++++++++++++++++++

3 files changed, 47 insertions(+), 18 deletions(-)
diff --git a/Makefile b/Makefile
@@ -83,3 +83,7 @@ cmd/df: cmd/df.c lib/humanize.c Makefile
 cmd/chmod: cmd/chmod.c lib/mode.c lib/symbolize_mode.c Makefile
 	rm -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
 	$(CC) -std=c99 $(CFLAGS) -o $@ cmd/chmod.c lib/mode.c lib/symbolize_mode.c $(LDFLAGS) $(LDSTATIC)
+
+cmd/seq: cmd/seq.c lib/absu.h Makefile
+	rm -f ${<:=.gcov} ${@:=.gcda} ${@:=.gcno}
+	$(CC) -std=c99 $(CFLAGS) -o $@ cmd/seq.c $(LDFLAGS) $(LDSTATIC)
diff --git a/cmd/seq.c b/cmd/seq.c
@@ -3,6 +3,8 @@
 // SPDX-License-Identifier: MPL-2.0
 
 #define _POSIX_C_SOURCE 200809L
+#include "../lib/absu.h"
+
 #include <errno.h>   // errno
 #include <stdbool.h> // bool, true, false
 #include <stdio.h>   // puts, fprintf
@@ -13,7 +15,7 @@ char *separator = "\n";
 bool zero_pad   = false;
 
 void
-seq(long i, long step, long last)
+seq(long i, unsigned long step, long last)
 {
 	if(i == last)
 	{
@@ -31,19 +33,6 @@ seq(long i, long step, long last)
 	}
 }
 
-static long unsigned int
-safe_labs(long int a)
-{
-	if(a >= 0)
-	{
-		return (long unsigned int)a;
-	}
-	else
-	{
-		return (long unsigned int)-a;
-	}
-}
-
 long
 get_num(char *str)
 {
@@ -91,9 +80,9 @@ main(int argc, char *argv[])
 	argc -= optind;
 	argv += optind;
 
-	long first = 1;
-	long step  = 1;
-	long last  = 1;
+	long first         = 1;
+	unsigned long step = 1;
+	long last          = 1;
 
 	switch(argc)
 	{
@@ -106,7 +95,7 @@ main(int argc, char *argv[])
 		break;
 	case 3:
 		first = get_num(argv[0]);
-		step  = (long)safe_labs(get_num(argv[1]));
+		step  = labsu(get_num(argv[1]));
 		last  = get_num(argv[2]);
 		break;
 	default:
diff --git a/lib/absu.h b/lib/absu.h
@@ -0,0 +1,36 @@
+// SPDX-FileCopyrightText: 2017 Haelwenn (lanodan) Monnier <contact+utils@hacktivis.me>
+// SPDX-License-Identifier: CC0-1.0 OR WTFPL
+
+// unsigned by definition reclaims the sign bit of their associated
+// signed representation, meaning you can always represent the absolute
+// values in an unsigned, even in two's complement where keeping
+// a signed representation would cause an error.
+//
+// Sadly the abs() family of functions in <stdint.h> is misdesigned
+
+extern unsigned int
+absu(int a)
+{
+	if(a >= 0)
+		return (unsigned int)a;
+	else
+		return (unsigned int)-a;
+}
+
+extern long unsigned int
+labsu(long int a)
+{
+	if(a >= 0)
+		return (long unsigned int)a;
+	else
+		return (long unsigned int)-a;
+}
+
+extern long long unsigned int
+llabsu(long long int a)
+{
+	if(a >= 0)
+		return (long long unsigned int)a;
+	else
+		return (long long unsigned int)-a;
+}