1 files changed, 132 insertions, 0 deletions
diff --git a/src/detection/cpucache/cpucache_linux.c b/src/detection/cpucache/cpucache_linux.c
new file mode 100644
index 0000000..0657c84
--- /dev/null
+++ b/src/detection/cpucache/cpucache_linux.c
@@ -0,0 +1,132 @@
+#include "cpucache.h"
+#include "common/io.h"
+#include "common/strutil.h"
+
+static const char* parseCpuCacheIndex(FFstrbuf* path, FFCPUCacheResult* result, FFstrbuf* buffer, FFstrbuf* added) {
+    uint32_t baseLen = path->length;
+    ffStrbufAppendS(path, "/level");
+    if (!ffReadFileBuffer(path->chars, buffer)) {
+        return "ffReadFileBuffer(\"/sys/devices/system/cpu/cpuX/cache/indexX/level\") == NULL";
+    }
+
+    uint32_t level = (uint32_t) ffStrbufToUInt(buffer, 0);
+    if (level < 1 || level > 4) {
+        return "level < 1 || level > 4";
+    }
+
+    ffStrbufSubstrBefore(path, baseLen);
+    ffStrbufAppendS(path, "/size");
+    if (!ffReadFileBuffer(path->chars, buffer)) {
+        return "ffReadFileBuffer(\"/sys/devices/system/cpu/cpuX/cache/indexX/size\") == NULL";
+    }
+
+    uint32_t sizeKb = (uint32_t) ffStrbufToUInt(buffer, 0);
+    if (sizeKb == 0) {
+        return "size == 0";
+    }
+
+    ffStrbufSubstrBefore(path, baseLen);
+    ffStrbufAppendS(path, "/type");
+    if (!ffReadFileBuffer(path->chars, buffer)) {
+        return "ffReadFileBuffer(\"/sys/devices/system/cpu/cpuX/cache/indexX/type\") == NULL";
+    }
+    ffStrbufTrimRightSpace(buffer);
+
+    FFCPUCacheType cacheType = 0;
+    switch (buffer->chars[0]) {
+        case 'I':
+            cacheType = FF_CPU_CACHE_TYPE_INSTRUCTION;
+            break;
+        case 'D':
+            cacheType = FF_CPU_CACHE_TYPE_DATA;
+            break;
+        case 'U':
+            cacheType = FF_CPU_CACHE_TYPE_UNIFIED;
+            break;
+        case 'T':
+            cacheType = FF_CPU_CACHE_TYPE_TRACE;
+            break;
+        default:
+            return "unknown cache type";
+    }
+
+    uint32_t lineSize = 0;
+    ffStrbufSubstrBefore(path, baseLen);
+    ffStrbufAppendS(path, "/coherency_line_size");
+    if (ffReadFileBuffer(path->chars, buffer)) {
+        lineSize = (uint32_t) ffStrbufToUInt(buffer, 0);
+    }
+
+    ffStrbufSubstrBefore(path, baseLen);
+    ffStrbufAppendS(path, "/shared_cpu_list");
+    ffStrbufClear(buffer);
+    ffStrbufAppendC(buffer, '[');
+    if (!ffAppendFileBuffer(path->chars, buffer)) {
+        return "ffAppendFileBuffer(\"/sys/devices/system/cpu/cpuX/cache/indexX/shared_cpu_list\") == NULL";
+    }
+    ffStrbufTrimRightSpace(buffer);
+
+    // deduplicate shared caches
+    ffStrbufAppendF(buffer, "_%u_%u_%u_%u]", level, sizeKb, lineSize, cacheType);
+
+    if (ffStrbufContain(added, buffer)) {
+        return NULL;
+    }
+    ffStrbufAppend(added, buffer);
+    ffCPUCacheAddItem(result, level, sizeKb * 1024, lineSize, cacheType);
+    return NULL;
+}
+
+static const char* parseCpuCache(FFstrbuf* path, FFCPUCacheResult* result, FFstrbuf* buffer, FFstrbuf* added) {
+    ffStrbufAppendS(path, "/cache/");
+    uint32_t baseLen = path->length;
+    FF_AUTO_CLOSE_DIR DIR* pathCacheDir = opendir(path->chars);
+    if (!pathCacheDir) {
+        return "opendir(\"/sys/devices/system/cpu/cpuX/cache/\") == NULL";
+    }
+
+    struct dirent* pathCacheEntry;
+    while ((pathCacheEntry = readdir(pathCacheDir)) != NULL) {
+        if (!ffStrStartsWith(pathCacheEntry->d_name, "index") || !ffCharIsDigit(pathCacheEntry->d_name[strlen("index")])) {
+            continue;
+        }
+
+        ffStrbufAppendS(path, pathCacheEntry->d_name);
+        const char* error = parseCpuCacheIndex(path, result, buffer, added);
+        if (error) {
+            return error;
+        }
+        ffStrbufSubstrBefore(path, baseLen);
+    }
+
+    return NULL;
+}
+
+const char* ffDetectCPUCache(FFCPUCacheResult* result) {
+    // https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-devices-system-cpu
+    FF_STRBUF_AUTO_DESTROY path = ffStrbufCreateS("/sys/devices/system/cpu/");
+    uint32_t baseLen = path.length;
+    FF_AUTO_CLOSE_DIR DIR* pathCpuDir = opendir(path.chars);
+    if (!pathCpuDir) {
+        return "opendir(\"/sys/devices/system/cpu/\") == NULL";
+    }
+
+    FF_STRBUF_AUTO_DESTROY buffer = ffStrbufCreate();
+    FF_STRBUF_AUTO_DESTROY added = ffStrbufCreate();
+
+    struct dirent* pathCpuEntry;
+    while ((pathCpuEntry = readdir(pathCpuDir)) != NULL) {
+        if (!ffStrStartsWith(pathCpuEntry->d_name, "cpu") ||
+            !ffCharIsDigit(pathCpuEntry->d_name[strlen("cpu")])) {
+            continue;
+        }
+
+        ffStrbufAppendS(&path, pathCpuEntry->d_name);
+        const char* error = parseCpuCache(&path, result, &buffer, &added);
+        if (error) {
+            return error;
+        }
+        ffStrbufSubstrBefore(&path, baseLen);
+    }
+    return NULL;
+}