Espresso 0.0.1c

drivers/fs/sfs.c

@@ -0,0 +1,94 @@
+#include <drivers/ide.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <fs/sfs.h>
+
+
+#define SFS_BEGINNING_LBA 8
+
+#pragma pack(push, 1)
+typedef struct sfs_file_header {
+  uint16_t magic; /* 0xBEEF */
+  /*
+    32 chars for the filename itself,
+    4 chars for the file's extension,
+    and 1 char for the null zero.
+  */
+  char filename[37];
+  
+  uint64_t data_beginning; /* Actually a 48 bit LBA mind you */
+  uint32_t num_sectors; /* Number of sectors after data_beginning that are this file's data */
+  
+  uint8_t padding[13]; /* Padding to 64 bytes total */
+} sfs_file_header_t;
+#pragma pack(pop)
+
+static sfs_file_header_t* base;
+
+
+
+
+int32_t sfs_init(bool format)
+{
+  uint8_t buffer[512] = { 0 };
+
+  int32_t kl = read_sector(SFS_BEGINNING_LBA, buffer);
+  
+  if (kl != 0)
+  {
+    return -1;
+  }
+  
+  volatile sfs_file_header_t null_file;
+  memcpy(&null_file, buffer, sizeof(sfs_file_header_t));
+  
+  if ((&null_file)->magic != 0xBEEF)
+  {
+    if (!format)
+    {
+      return -2;
+    }
+    
+    //sfs_format();
+    return -2;
+  }
+  
+  memcpy(base, &null_file, sizeof(sfs_file_header_t));
+  
+  return 0;
+}
+
+bool sfs_get_formatted_name(const char* raw_name, char output[37])
+{
+  size_t len = strlen(raw_name);
+
+  if (len > 36 || strchr(raw_name, '/') || strchr(raw_name, '*') || strchr(raw_name, '\\')) {
+    return false;
+  }
+
+  memset(output, ' ', 36);
+  output[36] = '\0';
+
+  memcpy(output, raw_name, len);
+
+  return true;
+}
+
+
+/* 
+  Note: if a negative value is passed for num, then read the whole file
+*/
+int32_t sfs_read_file(char* _name, void* buffer, uint32_t num)
+{
+  char name[37] = { '\0' };
+  
+  if (sfs_get_formatted_name(_name, name))
+  {
+    return -128;
+  }
+  
+  printf("%s", name);
+  
+  return 0;
+}