Refactor crossystem to move x86-specific implementation to its own file.

host/lib/host_misc.c

 /* Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  *
  * Host functions for verified boot.
  */
 
 /* TODO: change all 'return 0', 'return 1' into meaningful return codes */
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <unistd.h>
 
 #include "host_common.h"
 
 #include "cryptolib.h"
 #include "utility.h"
 #include "vboot_common.h"
 
 
+char* StrCopy(char* dest, const char* src, int dest_size) {
+  strncpy(dest, src, dest_size);
+  dest[dest_size - 1] = '\0';
+  return dest;
+}
+
+
 uint8_t* ReadFile(const char* filename, uint64_t* size) {
   FILE* f;
   uint8_t* buf;
 
   f = fopen(filename, "rb");
   if (!f) {
     VBDEBUG(("Unable to open file %s\n", filename));
     return NULL;
   }
 
@@ skipping 12 matching lines @@
     fclose(f);
     Free(buf);
     return NULL;
   }
 
   fclose(f);
   return buf;
 }
 
 
+char* ReadFileString(char* dest, int size, const char* filename) {
+  char* got;
+  FILE* f;
+
+  f = fopen(filename, "rt");
+  if (!f)
+    return NULL;
+
+  got = fgets(dest, size, f);
+  fclose(f);
+  return got;
+}
+
+
+int ReadFileInt(const char* filename) {
+  char buf[64];
+  int value;
+  char* e = NULL;
+
+  if (!ReadFileString(buf, sizeof(buf), filename))
+    return -1;
+
+  /* Convert to integer.  Allow characters after the int ("123 blah"). */
+  value = strtol(buf, &e, 0);
+  if (e == buf)
+    return -1;  /* No characters consumed, so conversion failed */
+
+  return value;
+}
+
+
+int ReadFileBit(const char* filename, int bitmask) {
+  int value = ReadFileInt(filename);
+  if (value == -1)
+    return -1;
+  else return (value & bitmask ? 1 : 0);
+}
+
+
 int WriteFile(const char* filename, const void *data, uint64_t size) {
   FILE *f = fopen(filename, "wb");
   if (!f) {
     VBDEBUG(("Unable to open file %s\n", filename));
     return 1;
   }
 
   if (1 != fwrite(data, size, 1, f)) {
     VBDEBUG(("Unable to write to file %s\n", filename));
     fclose(f);
     unlink(filename);  /* Delete any partial file */
   }
 
   fclose(f);
   return 0;
 }
 
 void PrintPubKeySha1Sum(VbPublicKey* key) {
   uint8_t* buf = ((uint8_t *)key) + key->key_offset;
   uint64_t buflen = key->key_size;
   uint8_t* digest = DigestBuf(buf, buflen, SHA1_DIGEST_ALGORITHM);
   int i;
   for (i=0; i<SHA1_DIGEST_SIZE; i++)
     printf("%02x", digest[i]);
   Free(digest);
 }