From f2ab77512354b3a1689eff8ecbdedd310e2e8119 Mon Sep 17 00:00:00 2001
From: Samanta Navarro <ferivoz@riseup.net>
Date: Sat, 24 Jul 2021 11:52:34 +0000
Subject: [PATCH] abuild: avoid calculations with void pointers

Arithmetic operations with void pointers are an extension by some
compilers and not part of the C standard, which does not specify the
size of void.

CFLAGS with -pedantic reveals this during compile time. I have adjusted
the usage of ?: so CFLAGS can contain -pedantic now.
---
 Makefile         |  2 +-
 abuild-gzsplit.c |  2 +-
 abuild-sudo.c    |  2 +-
 abuild-tar.c     | 10 ++++++----
 4 files changed, 9 insertions(+), 7 deletions(-)

diff --git a/Makefile b/Makefile
index a58e0b2..4c0a4b7 100644
--- a/Makefile
+++ b/Makefile
@@ -34,7 +34,7 @@ TAR		:= tar
 SCDOC		:= scdoc
 LINK		= $(CC) $(OBJS-$@) -o $@ $(LDFLAGS) $(LDFLAGS-$@) $(LIBS-$@)
 
-CFLAGS		?= -Wall -Werror -g
+CFLAGS		?= -Wall -Werror -g -pedantic
 
 SED_REPLACE	:= -e 's:@VERSION@:$(FULL_VERSION):g' \
 			-e 's:@prefix@:$(prefix):g' \
diff --git a/abuild-gzsplit.c b/abuild-gzsplit.c
index 9b171eb..ac55c54 100644
--- a/abuild-gzsplit.c
+++ b/abuild-gzsplit.c
@@ -75,7 +75,7 @@ int main(void)
 		}
 
 		if (zs.avail_in == 0 || r == Z_STREAM_END) {
-			len = (void *)zs.next_in - (void *)ibuf;
+			len = (char *)zs.next_in - (char *)ibuf;
 			if (write(fd, ibuf, len) != len) {
 				warn("Failed to write to %s", fn);
 				goto err;
diff --git a/abuild-sudo.c b/abuild-sudo.c
index 2c8dbcf..450e4ad 100644
--- a/abuild-sudo.c
+++ b/abuild-sudo.c
@@ -104,7 +104,7 @@ int main(int argc, const char *argv[])
 
 	if (name == NULL)
 		warnx("Could not find username for uid %d\n", uid);
-	setenv("USER", name ?: "", 1);
+	setenv("USER", name ? name : "", 1);
 
 	cmd = strrchr(argv[0], '/');
 	if (cmd)
diff --git a/abuild-tar.c b/abuild-tar.c
index 5964eac..44ebf17 100644
--- a/abuild-tar.c
+++ b/abuild-tar.c
@@ -122,15 +122,16 @@ static int usage(void)
 static ssize_t full_read(int fd, void *buf, size_t count)
 {
 	ssize_t total, n;
+	char *p = buf;
 
 	total = 0;
 	do {
-		n = read(fd, buf, count);
+		n = read(fd, p, count);
 		if (n < 0 && errno == EINTR)
 			continue;
 		if (n <= 0)
 			break;
-		buf += n;
+		p += n;
 		total += n;
 		count -= n;
 	} while (1);
@@ -144,15 +145,16 @@ static ssize_t full_read(int fd, void *buf, size_t count)
 static ssize_t full_write(int fd, const void *buf, size_t count)
 {
 	ssize_t total, n;
+	const char *p = buf;
 
 	total = 0;
 	do {
-		n = write(fd, buf, count);
+		n = write(fd, p, count);
 		if (n < 0 && errno == EINTR)
 			continue;
 		if (n <= 0)
 			break;
-		buf += n;
+		p += n;
 		total += n;
 		count -= n;
 	} while (1);