CS代考计算机代写 /* Grows two files in parallel and checks that their contents are

/* Grows two files in parallel and checks that their contents are
correct. */

#include
#include
#include “tests/lib.h”
#include “tests/main.h”

#define FILE_SIZE 8143
static char buf_a[FILE_SIZE];
static char buf_b[FILE_SIZE];

static void
write_some_bytes (const char *file_name, int fd, const char *buf, size_t *ofs)
{
if (*ofs < FILE_SIZE) { size_t block_size = random_ulong () % (FILE_SIZE / 8) + 1; size_t ret_val; if (block_size > FILE_SIZE – *ofs)
block_size = FILE_SIZE – *ofs;

ret_val = write (fd, buf + *ofs, block_size);
if (ret_val != block_size)
fail (“write %zu bytes at offset %zu in \”%s\” returned %zu”,
block_size, *ofs, file_name, ret_val);
*ofs += block_size;
}
}

void
test_main (void)
{
int fd_a, fd_b;
size_t ofs_a = 0, ofs_b = 0;

random_init (0);
random_bytes (buf_a, sizeof buf_a);
random_bytes (buf_b, sizeof buf_b);

CHECK (create (“a”, 0), “create \”a\””);
CHECK (create (“b”, 0), “create \”b\””);

CHECK ((fd_a = open (“a”)) > 1, “open \”a\””);
CHECK ((fd_b = open (“b”)) > 1, “open \”b\””);

msg (“write \”a\” and \”b\” alternately”);
while (ofs_a < FILE_SIZE || ofs_b < FILE_SIZE) { write_some_bytes ("a", fd_a, buf_a, &ofs_a); write_some_bytes ("b", fd_b, buf_b, &ofs_b); } msg ("close \"a\""); close (fd_a); msg ("close \"b\""); close (fd_b); check_file ("a", buf_a, FILE_SIZE); check_file ("b", buf_b, FILE_SIZE); }