Diff: TAR/tar.cpp

Revision:

1:121b61eeffe7

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TAR/tar.cpp	Wed Apr 08 14:52:09 2020 +0000
@@ -0,0 +1,53 @@
+#include "mbed.h"
+#include "tar.h"
+
+FILE* fopenTar(char *tarfile, char *namefile) { 
+    
+    int i;
+    char buf[32];
+    char sizeStr[12];
+    char *valExit = "error";
+    int size, offset = 0;
+    
+    FILE *Tar = fopen(tarfile, "r");
+    
+    while(!feof(Tar)) {
+        for(i=0; i <= strlen(namefile); i++) buf[i] = fgetc(Tar);
+        
+        if(!strcmp(buf, namefile)) {
+            valExit = "";
+            break;
+        }
+        
+        fseek(Tar , 124+offset , SEEK_SET);
+        for(i=0; i < 12; i++) sizeStr[i] = fgetc(Tar);
+        //printf("size string: %s; octal: %d; dec.: %x\n", sizeStr, atoi(sizeStr), oct2dec(atoi(sizeStr)) );
+        
+        size = oct2dec(atoi(sizeStr));
+        if(offset % 512 != 0) offset += (size/512 + 2)*512;
+        else offset += (size/512 + 1)*512;
+        
+        fseek(Tar , offset , SEEK_SET);  
+    }
+    
+    if(valExit == "error") {
+        printf("file \"%s\" not find in tar\n", namefile); 
+        return NULL;
+    } else {
+        fseek(Tar, offset+512 , SEEK_SET);
+        return Tar;
+    }
+}
+
+int oct2dec(int n) /* Function to convert octal to decimal */
+{
+    int decimal=0, i=0, rem;
+    while (n!=0)
+    {
+        rem = n%10;
+        n/=10;
+        decimal += rem*pow(8.0,i);
+        ++i;
+    }
+    return decimal;
+}
\ No newline at end of file