[Debian-med-packaging] Bug#1068573: libmaus2: fix error caused by sysconf function

[wuruilong]

Source: libmaus2
Severity: normal
X-Debbugs-Cc: wuruilong at loongson.cn

Dear Maintainer,

Some architectures in glibc do not define the sysconf.c file, and using the generic posix sysconf.c file to call the _SC_LEVEL1_DCACHE_LINESIZE variable returns 0 by default, which leads to failure of the test in loongarch, ia64, s390x and other architectures, the detailed error link is as follows: https://buildd.debian.org/status/fetch.php?pkg=libmaus2&arch=loong64&ver=2.0.813%2Bds-1%2Bb1&stamp=1710143471&raw=0
This patch reference lscpu code to read the data in coherency_line_size file directly can fix the above error, and it passes the test on x86 and loongarch.

wuruilong

-- System Information:
Debian Release: trixie/sid
  APT prefers unreleased
  APT policy: (500, 'unreleased'), (500, 'unstable')
Architecture: loong64 (loongarch64)

Kernel: Linux 5.10.0-60.96.0.126.oe2203.loongarch64 (SMP w/32 CPU threads)
Locale: LANG=C, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set
Shell: /bin/sh linked to /usr/bin/dash
Init: unable to detect
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 libmaus2 (2.0.813+ds-1) unstable; urgency=medium
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--- libmaus2-2.0.813+ds.orig/src/libmaus2/arch/CacheLineSize.cpp
+++ libmaus2-2.0.813+ds/src/libmaus2/arch/CacheLineSize.cpp
@@ -17,6 +17,7 @@
 */
 #include <libmaus2/arch/CacheLineSize.hpp>
 #include <stdexcept>
+#include <stdio.h>
 
 #include <libmaus2/LibMausConfig.hpp>
 
@@ -39,10 +40,18 @@ std::atomic<unsigned int> libmaus2::arch
 /**
  * @return size of a (level 1) cache line in bytes
  **/
-#if defined(LIBMAUS2_HAVE_SYSCONF) && defined(_SC_LEVEL1_DCACHE_LINESIZE)
+#if defined(__linux__)
 static uint64_t getCacheLineSizeLocal()
 {
-	return sysconf(_SC_LEVEL1_DCACHE_LINESIZE);
+	FILE *fp = NULL;
+	fp = fopen("/sys/devices/system/cpu/cpu0/cache/index0/coherency_line_size", "r");
+	uint64_t i = 0;
+	if(fp){
+		fscanf(fp, "%d", &i);
+		fclose(fp);
+	}
+	return i;
 }
 #elif defined(_WIN32)
 static uint64_t getCacheLineSizeLocal()