From: Michael Tremer <michael.tremer@ipfire.org>
Date: Sat, 28 Oct 2023 10:52:24 +0000 (+0000)
Subject: os: Implement getting memory stats from /proc/meminfo
X-Git-Tag: 0.9.30~1382
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=1d29d610616d2dff3eda0dbfdd1669e24d1f7bbf;p=pakfire.git

os: Implement getting memory stats from /proc/meminfo

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/include/pakfire/os.h b/src/libpakfire/include/pakfire/os.h
index 8cf6021e3..dd600e633 100644
--- a/src/libpakfire/include/pakfire/os.h
+++ b/src/libpakfire/include/pakfire/os.h
@@ -23,6 +23,8 @@
 
 #ifdef PAKFIRE_PRIVATE
 
+#include <stdint.h>
+
 // CPU info
 
 #define CPU_VENDOR_MAX 16
@@ -35,6 +37,26 @@ struct pakfire_cpuinfo {
 
 int pakfire_cpuinfo(struct pakfire_cpuinfo* cpuinfo);
 
+// Meminfo
+
+struct pakfire_meminfo {
+	uint64_t total;
+	uint64_t used;
+	uint64_t free;
+	uint64_t available;
+	uint64_t buffers;
+	uint64_t cached;
+	uint64_t active;
+	uint64_t inactive;
+
+	// Swap
+	uint64_t swap_total;
+	uint64_t swap_used;
+	uint64_t swap_free;
+};
+
+int pakfire_meminfo(struct pakfire_meminfo* meminfo);
+
 #endif /* PAKFIRE_PRIVATE */
 
 #endif /* PAKFIRE_OS_H */
diff --git a/src/libpakfire/os.c b/src/libpakfire/os.c
index 66d03789f..63a225e66 100644
--- a/src/libpakfire/os.c
+++ b/src/libpakfire/os.c
@@ -20,6 +20,7 @@
 
 #include <ctype.h>
 #include <errno.h>
+#include <limits.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -139,3 +140,105 @@ static int pakfire_parse_cpuinfo(char* line, size_t length, void* data) {
 int pakfire_cpuinfo(struct pakfire_cpuinfo* cpuinfo) {
 	return pakfire_parse_file("/proc/cpuinfo", pakfire_parse_cpuinfo, cpuinfo);
 }
+
+// Meminfo
+
+static int pakfire_parse_meminfo_value(uint64_t* mem, const char* s) {
+	char* remainder = NULL;
+	uint64_t m = 0;
+
+	// Parse the numeric value
+	m = strtoul(s, &remainder, 10);
+	if (m == ULONG_MAX)
+		return -errno;
+
+	// Convert into bytes
+	if (strcmp(remainder, " kB") == 0) {
+		// Check if the multiplication won't overflow
+		if (m > UINT64_MAX / 1024)
+			return -EOVERFLOW;
+
+		m *= 1024;
+
+	// Fail on anything else
+	} else if (*remainder)
+		return -EINVAL;
+
+	// Store the value
+	*mem = m;
+
+	return 0;
+}
+
+static int pakfire_parse_meminfo(char* line, size_t length, void* data) {
+	struct pakfire_meminfo* meminfo = data;
+	int r;
+
+	// Key & Value
+	const char* k = NULL;
+	const char* v = NULL;
+
+	// Split the line
+	r = pakfire_split_line(line, length, &k, &v);
+	if (r)
+		return r;
+
+	// If we didn't get a result we skip this line
+	if (!k || !v)
+		return 0;
+
+	// Total
+	if (strcmp(k, "MemTotal") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->total, v);
+
+	// Free
+	else if (strcmp(k, "MemFree") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->free, v);
+
+	// Available
+	else if (strcmp(k, "MemAvailable") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->available, v);
+
+	// Buffers
+	else if (strcmp(k, "Buffers") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->buffers, v);
+
+	// Cached
+	else if (strcmp(k, "Cached") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->cached, v);
+
+	// Active
+	else if (strcmp(k, "Active") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->active, v);
+
+	// Inactive
+	else if (strcmp(k, "Inactive") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->inactive, v);
+
+	// Swap Total
+	else if (strcmp(k, "SwapTotal") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->swap_total, v);
+
+	// Swap Free
+	else if (strcmp(k, "SwapFree") == 0)
+		return pakfire_parse_meminfo_value(&meminfo->swap_free, v);
+
+	return 0;
+}
+
+int pakfire_meminfo(struct pakfire_meminfo* meminfo) {
+	int r;
+
+	// Parse /proc/meminfo
+	r = pakfire_parse_file("/proc/meminfo", pakfire_parse_meminfo, meminfo);
+	if (r)
+		return r;
+
+	// Set used memory
+	meminfo->used = meminfo->total - meminfo->free;
+
+	// Set used swap
+	meminfo->swap_used = meminfo->swap_total - meminfo->swap_free;
+
+	return 0;
+}
diff --git a/tests/libpakfire/os.c b/tests/libpakfire/os.c
index 940aec589..e631bad1e 100644
--- a/tests/libpakfire/os.c
+++ b/tests/libpakfire/os.c
@@ -38,8 +38,34 @@ FAIL:
 	return EXIT_FAILURE;
 }
 
+// This test parses /proc/meminfo
+static int test_meminfo(const struct test* t) {
+	struct pakfire_meminfo meminfo = {};
+
+	ASSERT_SUCCESS(pakfire_meminfo(&meminfo));
+
+	// We can only check is something has been read
+	ASSERT(meminfo.total > 0);
+	ASSERT(meminfo.used > 0);
+	ASSERT(meminfo.free > 0);
+	ASSERT(meminfo.available > 0);
+	ASSERT(meminfo.buffers > 0);
+	ASSERT(meminfo.cached > 0);
+	ASSERT(meminfo.active > 0);
+	ASSERT(meminfo.inactive > 0);
+	ASSERT(meminfo.swap_total >= 0);
+	ASSERT(meminfo.swap_used >= 0);
+	ASSERT(meminfo.swap_free >= 0);
+
+	return EXIT_SUCCESS;
+
+FAIL:
+	return EXIT_FAILURE;
+}
+
 int main(int argc, const char* argv[]) {
 	testsuite_add_test(test_cpuinfo);
+	testsuite_add_test(test_meminfo);
 
 	return testsuite_run(argc, argv);
 }