From: Helge Deller <deller@gmx.de>
Subject: [klibc] Add pread and pwrite 32bit syscall wrappers for parisc
Date: Wed, 23 Apr 2014 22:52:53 +0200
Bug-Debian: https://bugs.debian.org/745660
Forwarded: http://www.zytor.com/pipermail/klibc/2016-January/003880.html

On the hppa arch (32bit userspace and 32 or 64bit kernel), the fstype
program fails to detect the filesystem.  The reason for this failure
is, that fstype calls the pread() syscall, which has on some
architectures with 32bit userspace a different calling syntax.  I
noticed this bug on hppa, but I assume s390 (32bit) and others might
run into similiar issues.

Signed-off-by: Helge Deller <deller@gmx.de>
---
--- a/usr/include/endian.h
+++ b/usr/include/endian.h
@@ -12,4 +12,10 @@
 #define PDP_ENDIAN	__PDP_ENDIAN
 #define BYTE_ORDER	__BYTE_ORDER
 
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+# define __LONG_LONG_PAIR(HI, LO) LO, HI
+#elif __BYTE_ORDER == __BIG_ENDIAN
+# define __LONG_LONG_PAIR(HI, LO) HI, LO
+#endif
+
 #endif				/* _ENDIAN_H */
--- a/usr/klibc/Kbuild
+++ b/usr/klibc/Kbuild
@@ -35,6 +35,7 @@ klib-y += vsnprintf.o snprintf.o vsprint
 	  siglongjmp.o \
 	  sigaction.o sigpending.o sigprocmask.o sigsuspend.o \
 	  pselect.o ppoll.o \
+	  pread.o pwrite.o \
 	  brk.o sbrk.o malloc.o realloc.o zalloc.o calloc.o \
 	  mmap.o shm_open.o shm_unlink.o \
 	  memcpy.o memcmp.o memset.o memccpy.o memmem.o memswap.o \
--- /dev/null
+++ b/usr/klibc/pread.c
@@ -0,0 +1,29 @@
+/*
+ * pread.c
+ *
+ * Some architectures need to wrap the system call
+ */
+
+#include <endian.h>
+#include <sys/syscall.h>
+
+#if defined(__hppa__)
+
+#if _BITSIZE == 32
+extern size_t __pread(int, void *, size_t, unsigned int, unsigned int);
+#else
+extern size_t __pread(int, void *, size_t, off_t);
+#endif
+
+size_t pread(int fd, void *buf, size_t count, off_t offset)
+{
+#if _BITSIZE == 32
+	unsigned int hi = offset >> 32;
+	unsigned int lo = (unsigned int) offset;
+	return __pread(fd, buf, count, __LONG_LONG_PAIR(hi, lo));
+#else
+	return __pread(fd, buf, count, offset);
+#endif
+}
+
+#endif
--- /dev/null
+++ b/usr/klibc/pwrite.c
@@ -0,0 +1,29 @@
+/*
+ * pwrite.c
+ *
+ * Some architectures need to wrap the system call
+ */
+
+#include <endian.h>
+#include <sys/syscall.h>
+
+#if defined(__hppa__)
+
+#if _BITSIZE == 32
+extern ssize_t __pwrite(int, const void *, size_t, unsigned int, unsigned int);
+#else
+extern ssize_t __pwrite(int, const void *, size_t, off_t);
+#endif
+
+size_t pwrite(int fd, void *buf, size_t count, off_t offset)
+{
+#if _BITSIZE == 32
+	unsigned int hi = offset >> 32;
+	unsigned int lo = (unsigned int) offset;
+	return __pwrite(fd, buf, count, __LONG_LONG_PAIR(hi, lo));
+#else
+	return __pwrite(fd, buf, count, offset);
+#endif
+}
+
+#endif
--- a/usr/klibc/SYSCALLS.def
+++ b/usr/klibc/SYSCALLS.def
@@ -189,8 +189,10 @@ int fdatasync,fsync::fdatasync(int);
 int readv(int, const struct iovec *, int);
 int writev(int, const struct iovec *, int);
 int ftruncate64,ftruncate::ftruncate(int, off_t);
-ssize_t pread64,pread::pread(int, void *, size_t, off_t);
-ssize_t pwrite64,pwrite::pwrite(int, void *, size_t, off_t);
+<parisc> ssize_t pread64,pread::__pread(int, void *, size_t, off_t);
+<parisc> ssize_t pwrite64,pwrite::__pwrite(int, void *, size_t, off_t);
+<!parisc> ssize_t pread64,pread::pread(int, void *, size_t, off_t);
+<!parisc> ssize_t pwrite64,pwrite::pwrite(int, void *, size_t, off_t);
 int sync_file_range,fdatasync,fsync::sync_file_range(int, off_t, off_t, unsigned int);
 <?> int splice(int, off_t *, int, off_t *, size_t, unsigned int);
 <?> int tee(int, int, size_t, unsigned int);