WIP large file support

[yaffs2.git] / linux-tests / writebigsparse.c

diff --git a/linux-tests/writebigsparse.c b/linux-tests/writebigsparse.c
new file mode 100644 (file)
index 0000000..0d70128
--- /dev/null
+++ b/linux-tests/writebigsparse.c
@@ -0,0 +1,80 @@
+#define _LARGEFILE64_SOURCE
+#include<stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+
+int handle;
+
+#define N_WRITES 8000
+#define STRIDE  1000
+
+#define BUFFER_N 2000
+unsigned  buffer[BUFFER_N];
+
+
+void set_buffer(int n)
+{
+       int i;
+       for(i = 0; i < BUFFER_N; i++)
+               buffer[i] = i + n;
+}
+
+void write_big_sparse_file(int h)
+{
+       int i;
+       off64_t offset = 0;
+       off64_t pos;
+       int n = sizeof(buffer);
+       int wrote;
+       
+       for(i = 0; i < 4000; i++) {
+               set_buffer(i);
+               pos = lseek64(h, offset, SEEK_SET);
+               if(pos != offset) {
+                       printf("mismatched seek pos %lld offset %lld\n",
+                               pos, offset);
+                       exit(1);
+               }
+               wrote = write(h, buffer, n);
+               
+               if(wrote != n) {
+                       printf("mismatched write wrote %d n %d\n", wrote, n);
+                       exit(1);
+               }
+               
+               offset += (STRIDE * sizeof(buffer));
+       }
+}
+
+
+
+
+void verify_big_sparse_file(int h)
+{
+}
+
+int main(int argc, char *argv[])
+{
+
+       if(argc < 2) {
+               printf("Gimme a file name!\n");
+               exit(1);
+       }
+       
+       handle = open(argv[1], O_CREAT | O_RDWR | O_TRUNC, S_IREAD | S_IWRITE);
+       
+       if(handle < 0) {
+               perror("opening file");
+               exit(1);
+       }
+       
+       write_big_sparse_file(handle);
+       system("sudo echo 3 > /proc/sys/vm/drop_caches");
+       verify_big_sparse_file(handle);
+       
+       printf("Job done\n");
+       return 0;
+}