Add fallback in Linux in case we cant get the freq from cpuid, using udev (welcome back, udev...)

Makefile

@@ -7,6 +7,11 @@ SRC_DIR=src/
 SOURCE=$(SRC_DIR)main.c $(SRC_DIR)standart.c $(SRC_DIR)extended.c $(SRC_DIR)cpuid.c $(SRC_DIR)printer.c $(SRC_DIR)args.c $(SRC_DIR)global.c
 HEADERS=$(SRC_DIR)standart.h $(SRC_DIR)extended.h  $(SRC_DIR)cpuid.h $(SRC_DIR)printer.h $(SRC_DIR)ascii.h $(SRC_DIR)args.h $(SRC_DIR)global.h
 
+ifneq ($(OS),Windows_NT)
+	SOURCE += $(SRC_DIR)udev.c
+	HEADERS += $(SRC_DIR)udev.h
+endif
+
 OUTPUT=cpufetch
 
 all: $(OUTPUT)

src/main.c

@@ -24,7 +24,7 @@ Peak FLOPS:  512 GFLOP/s(in simple precision)
 
 ***/
 
-static const char* VERSION = "0.45";
+static const char* VERSION = "0.46";
 
 void print_help(int argc, char *argv[]) {
   printf("Usage: %s [--version] [--help] [--style STYLE]\n\

src/standart.c

@@ -9,6 +9,10 @@
 #include "cpuid.h"
 #include "global.h"
 
+#ifndef _WIN32
+#include "udev.h"
+#endif
+
 #define VENDOR_INTEL_STRING "GenuineIntel"
 #define VENDOR_AMD_STRING   "AuthenticAMD"
 
@@ -21,8 +25,6 @@
 #define STRING_KILOBYTES  "KB"
 #define STRING_MEGABYTES  "MB"
 
-#define UNKNOWN -1
-
 /*
  * cpuid reference: http://www.sandpile.org/x86/cpuid.htm
  */
@@ -346,9 +348,15 @@ struct frequency* get_frequency_info(struct cpuInfo* cpu) {
   struct frequency* freq = malloc(sizeof(struct frequency));
   
   if(cpu->maxLevels < 0x16) {
+    #ifdef _WIN32
       printErr("Can't read frequency information from cpuid (needed level is %d, max is %d)", 0x16, cpu->maxLevels);
       freq->base = UNKNOWN;
       freq->max = UNKNOWN;
+    #else
+      printWarn("Can't read frequency information from cpuid (needed level is %d, max is %d). Using udev", 0x16, cpu->maxLevels);
+      freq->base = 0;
+      freq->max = get_max_freq_from_file();
+    #endif
   }
   else {
     unsigned int eax = 0x16;
@@ -436,7 +444,7 @@ char* get_str_peak_performance(struct cpuInfo* cpu, struct topology* topo, long
   
   // Intel USUALLY has two VPUs. I have never seen an AMD 
   // with two VPUs.
-  if(cpu->VENDOR == VENDOR_INTEL) flops = flops * 2; 
+  if(cpu->cpu_vendor == VENDOR_INTEL) flops = flops * 2; 
 
   if(cpu->FMA3 || cpu->FMA4)
     flops = flops*2;

src/standart.h

@@ -6,6 +6,8 @@
 #define VENDOR_AMD     2
 #define VENDOR_INVALID 3
 
+#define UNKNOWN -1
+
 struct cpuInfo;
 struct frequency;
 struct cache;

src/udev.c

@@ -0,0 +1,71 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "global.h"
+#include "standart.h"
+
+#define _PATH_SYS_SYSTEM    "/sys/devices/system"
+#define _PATH_SYS_CPU       _PATH_SYS_SYSTEM"/cpu"
+#define _PATH_ONE_CPU       _PATH_SYS_CPU"/cpu0"
+
+#define _PATH_FREQUENCY     _PATH_ONE_CPU"/cpufreq"
+#define _PATH_FREQUENCY_MAX _PATH_FREQUENCY"/cpuinfo_max_freq"
+#define _PATH_FREQUENCY_MIN _PATH_FREQUENCY"/cpuinfo_min_freq"
+
+#define DEFAULT_FILE_SIZE 4096
+
+long get_freq_from_file(char* path) {
+  FILE *file = fopen(path, "r");
+
+  if(file == NULL) {
+    perror("fopen");
+    printBug("Could not open '%s'", path);
+    return UNKNOWN;
+  }
+
+  //File exists, read it
+  int fd = fileno(file);
+  int bytes_read = 0;
+  int offset = 0;
+  int block = 1;
+  char* buf = malloc(sizeof(char)*DEFAULT_FILE_SIZE);
+  memset(buf, 0, sizeof(char)*DEFAULT_FILE_SIZE);
+
+  while (  (bytes_read = read(fd, buf+offset, block)) > 0 ) {
+    offset += bytes_read;
+  }
+
+  char* end;
+  errno = 0;
+  long ret = strtol(buf, &end, 10);
+  if(errno != 0) {
+    perror("strtol");
+    printBug("Failed parsing '%s' file. Read data was: '%s'", path, buf);
+    free(buf);
+    return UNKNOWN;
+  }
+  
+  // We will be getting the frequency in KHz
+  // We consider it is an error if frequency is
+  // greater than 10 GHz or less than 100 MHz
+  if(ret > 10000 * 1000 || ret <  100 * 1000) {
+    printBug("Invalid data was read from file '%s': %ld\n", path, ret);
+    return UNKNOWN;
+  }
+  
+  free(buf);
+  fclose(file);
+  
+  return ret/1000;
+}
+
+long get_max_freq_from_file() {
+  return get_freq_from_file(_PATH_FREQUENCY_MAX);
+}
+
+long get_min_freq_from_file() {
+  return get_freq_from_file(_PATH_FREQUENCY_MIN);
+}

src/udev.h

@@ -0,0 +1,7 @@
+#ifndef __UDEV__
+#define __UDEV__
+
+long get_max_freq_from_file();
+long get_min_freq_from_file();
+
+#endif