Better error messages for memory & swap

src/detection/memory/memory.c

@@ -5,6 +5,9 @@ void ffDetectMemoryImpl(FFMemoryResult* memory);
 
 static void calculatePercentage(FFMemoryStorage* storage)
 {
+    if(storage->error.length == 0)
+        return;
+
     if(storage->bytesTotal == 0)
         storage->percentage = 0;
     else
@@ -14,6 +17,9 @@ static void calculatePercentage(FFMemoryStorage* storage)
 const FFMemoryResult* ffDetectMemory()
 {
     FF_DETECTION_INTERNAL_GUARD(FFMemoryResult,
+        ffStrbufInitA(&result.ram.error, 0);
+        ffStrbufInitA(&result.swap.error, 0);
+
         ffDetectMemoryImpl(&result);
         calculatePercentage(&result.ram);
         calculatePercentage(&result.swap);

src/detection/memory/memory.h

@@ -7,6 +7,7 @@
 
 typedef struct FFMemoryStorage
 {
+    FFstrbuf error;
     uint64_t bytesUsed;
     uint64_t bytesTotal;
     uint8_t percentage;

src/detection/memory/memory_apple.c

@@ -4,27 +4,49 @@
 #include <string.h>
 #include <mach/mach.h>
 
-void ffDetectMemoryImpl(FFMemoryResult* memory)
+static void detectRam(FFMemoryStorage* ram)
 {
-    memset(memory, 0, sizeof(FFMemoryResult));
-
     memory->ram.bytesTotal = (uint64_t) ffSysctlGetInt64("hw.memsize", 0);
+    if(ram->bytesTotal == 0)
+    {
+        ffStrbufAppendS(&ram->error, "Failed to read hw.memsize");
+        return;
+    }
 
     uint32_t pagesize = (uint32_t) ffSysctlGetInt("hw.pagesize", 0);
     if(pagesize == 0)
+    {
+        ffStrbufAppendS(&ram->error, "Failed to read hw.pagesize");
         return;
+    }
 
     mach_msg_type_number_t count = HOST_VM_INFO_COUNT;
     vm_statistics_data_t vmstat;
     if(host_statistics(mach_host_self(), HOST_VM_INFO, (host_info_t) (&vmstat), &count) != KERN_SUCCESS)
+    {
+        ffStrbufAppendS(&ram->error, "Failed to read vm statistics");
         return;
+    }
 
     memory->ram.bytesUsed = ((uint64_t) vmstat.active_count + vmstat.wire_count) * pagesize;
+}
 
+static void detectSwap(FFMemoryStorage* swap)
+{
     struct xsw_usage swap;
     size_t size = sizeof(swap);
-    if (sysctlbyname("vm.swapusage", &swap, &size, 0, 0) == -1)
+    if(sysctlbyname("vm.swapusage", &swap, &size, 0, 0) != 0)
+    {
+        ffStrbufAppendS(&swap->error, "Failed to read vm.swapusage");
         return;
+    }
+
     memory->swap.bytesTotal = swap.xsu_total;
     memory->swap.bytesUsed = swap.xsu_used;
 }
+
+void ffDetectMemoryImpl(FFMemoryResult* memory)
+{
+    detectRam(&memory->ram);
+    detectSwap(&memory->swap);
+}

src/detection/memory/memory_bsd.c

@@ -1,17 +1,34 @@
 #include "memory.h"
 #include "common/sysctl.h"
 
-void ffDetectMemoryImpl(FFMemoryResult* memory)
+static void detectRam(FFMemoryStorage* ram)
 {
     uint32_t pageSize = (uint32_t) ffSysctlGetInt("hw.pagesize", 0);
+    if(pageSize == 0)
+    {
+        ffStrbufAppendS(&ram->error, "Failed to read hw.pagesize");
+        return;
+    }
 
     memory->ram.bytesTotal = (uint64_t) ffSysctlGetInt64("vm.stats.vm.v_page_count", 0) * pageSize;
-    
+    if(ram->bytesTotal == 0)
+    {
+        ffStrbufAppendS(&ram->error, "Failed to read vm.stats.vm.v_page_count");
+        return;
+    }
+
     memory->ram.bytesUsed = memory->ram.bytesTotal
         - (uint64_t) ffSysctlGetInt64("vm.stats.vm.v_free_count", 0) * pageSize
         - (uint64_t) ffSysctlGetInt64("vm.stats.vm.v_inactive_count", 0) * pageSize
     ;
-
-    memory->swap.bytesTotal = 0;
-    memory->swap.bytesUsed = 0;
+}
+
+static void detectSwap(FFMemoryStorage* swap)
+{
+    ffStrbufAppendS(&swap->error, "Not implemented");
+}
+void ffDetectMemoryImpl(FFMemoryResult* memory)
+{
+    detectRam(&memory->ram);
+    detectSwap(&memory->swap);
 }

src/detection/memory/memory_linux.c

@@ -5,11 +5,13 @@
 
 void ffDetectMemoryImpl(FFMemoryResult* memory)
 {
-    memset(memory, 0, sizeof(FFMemoryResult));
-
     FILE* meminfo = fopen("/proc/meminfo", "r");
     if(meminfo == NULL)
+    {
+        ffStrbufAppendS(&memory->ram.error, "Failed to open /proc/meminfo");
+        ffStrbufAppendS(&memory->swap.error, "Failed to open /proc/meminfo");
         return;
+    }
 
     char* line = NULL;
     size_t len = 0;
@@ -41,7 +43,10 @@ void ffDetectMemoryImpl(FFMemoryResult* memory)
     fclose(meminfo);
 
     memory->ram.bytesTotal = memTotal * (uint64_t) 1024;
-    memory->ram.bytesUsed = (memTotal + shmem - memFree - buffers - cached - sReclaimable) * (uint64_t) 1024;
+    if(memory->ram.bytesTotal == 0)
+        ffStrbufAppendS(&memory->ram.error, "Failed to read MemTotal");
+    else
+        memory->ram.bytesUsed = (memTotal + shmem - memFree - buffers - cached - sReclaimable) * (uint64_t) 1024;
 
     memory->swap.bytesTotal = swapTotal * (uint64_t) 1024;
     memory->swap.bytesUsed = (swapTotal - swapFree) * (uint64_t) 1024;

src/modules/memory.c

@@ -10,9 +10,9 @@
 
 static void printMemory(FFinstance* instance, const char* name, const FFModuleArgs* moduleArgs, const FFMemoryStorage* storage)
 {
-    if(storage->bytesUsed == 0 && storage->bytesTotal == 0)
+    if(storage->error.length > 0)
     {
-        ffPrintError(instance, name, 0, moduleArgs, "Failed to detect memory");
+        ffPrintError(instance, name, 0, moduleArgs, "%s", storage->error.chars);
         return;
     }