double indirect block support to ELF and check sum calc

1 files changed, 51 insertions, 8 deletions

diff --git a/fs/ext2.c b/fs/ext2.c
index 27fe31e..7322da2 100644
--- a/fs/ext2.c
+++ b/fs/ext2.c
@@ -153,6 +153,31 @@ ext2_inode ext2_get_inode(uint8_t *ram,int inode_num)
 
 }
 
+void* ext2_get_blockstart(void* start, uint32_t block_size, uint32_t block_idx)
+{
+    return (start+block_size*block_idx);
+}
+
+void* ext2_get_indirectstart(void *start, uint32_t block_size, uint32_t indirect1_idx, uint32_t block_idx)
+{
+    uint32_t *indirect_ptr=ext2_get_blockstart(start,block_size,indirect1_idx);
+    void *ptr=ext2_get_blockstart(start,block_size,indirect_ptr[block_idx]); 
+    return ptr;
+}
+
+void* ext2_get_indirectstart_double(void *start, uint32_t block_size, uint32_t indirect2_idx, uint32_t block_idx)
+{
+
+    //doubly indirect list
+    uint32_t *dil=ext2_get_blockstart(start,block_size,indirect2_idx);
+
+    int indirect1_idx=block_idx/(block_size/4);
+    int idx=block_idx%(block_size/4);
+
+    //log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"bl: %d : %d / %d",block_idx,indirect1_idx, idx);
+
+    return ext2_get_indirectstart(start,block_size,dil[indirect1_idx],idx);
+}
 
 int ext2_inode_content(char *ram,int inode_nr,uint8_t *ramdest,int max)
 {
@@ -162,31 +187,48 @@ int ext2_inode_content(char *ram,int inode_nr,uint8_t *ramdest,int max)
     int block=0;
     int block_size=1024;
     int block_counter=0;
-    uint8_t *ptr=ram+block_size*inode.direct_pointer[0]; 
+    uint8_t *ptr=ext2_get_blockstart(ram,block_size,inode.direct_pointer[0]); 
+    int sum=0;
+    int count=0;
 
     log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Loading %d %d bytes",inode.size_high, inode.size_low);
-    while(pos<inode.size_low) // use size high?
+
+    while(pos<inode.size_low) // TODO: use size high!
     {
 	ramdest[pos]=*ptr;
+		    
+	sum = (sum >> 1) + ((sum & 1) << 15);
+	sum+=(int)*ptr;
+	sum&=0xffff;
+	count++;
 
 	ptr++;
 	block_counter++;
 	pos++;
+
 	if(block_counter>=block_size)
 	{
 	    block++;
 
-	    if(block>=12)
+	    if(block<12)
 	    {
-		int indirect_block=block-12;
-		uint32_t *indirect_ptr=ram+block_size*inode.indirect1;
-	  	ptr=ram+block_size*indirect_ptr[indirect_block]; 
+	  	    ptr=ext2_get_blockstart(ram,block_size,inode.direct_pointer[block]);
 
 	    }
+	    else if(block-12<block_size/4)
+	    {
+	  	    ptr=ext2_get_indirectstart(ram,block_size,inode.indirect1,block-12);
+	    }
+	    
+	    else if(block-12-block_size/4<1024/4*1024/4)
+	    {
+	  	ptr=ext2_get_indirectstart_double(ram,block_size,inode.indirect2,block-12-block_size/4);
+	    }
 	    else
 	    {
-	  	    ptr=ram+block_size*inode.direct_pointer[block]; 
+		panic(FOOLOS_MODULE_NAME,"Triplu Indirect Block Pointers not supported yet, file is too big to load, sorry!");
 	    }
+	    
 
 	    block_counter=0;
 	}
@@ -194,7 +236,8 @@ int ext2_inode_content(char *ram,int inode_nr,uint8_t *ramdest,int max)
 	
 
     }
-//  if(block>=12)panic(FOOLOS_MODULE_NAME,"such big files unsupported yet");
+    log(FOOLOS_MODULE_NAME,FOOLOS_LOG_INFO,"Fool Check Sum: 0x%08X for %d bytes",sum,count);
+
 }
 
 int ext2_read_dir(uint8_t *ram, int inode_nr,fs_dirent *dirs,int max)