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// RUN: %clangxx -g %s -o %t && %run %t | FileCheck %s
// CHECK: READ CALLED; len={{[0-9]*}}
// CHECK-NEXT: READ: test
// CHECK-NEXT: WRITE CALLED: test
// CHECK-NEXT: READ CALLED; len={{[0-9]*}}
// CHECK-NEXT: READ: test
// CHECK-NEXT: WRITE CALLED: test
// CHECK-NEXT: CLOSE CALLED
// CHECK-NEXT: SEEK CALLED; off=100, whence=0
// CHECK-NEXT: READ CALLED; len={{[0-9]*}}
// CHECK-NEXT: READ: test
// CHECK-NEXT: WRITE CALLED: test
// CHECK-NEXT: FLUSH CALLED
// CHECK-NEXT: WRITE CALLED: test
// CHECK-NEXT: FLUSH CALLED
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int cookie_var;
ssize_t f_read(void *cookie, void *buf, size_t len) {
assert(cookie == &cookie_var);
assert(len >= 6);
printf("READ CALLED; len=%zd\n", len);
return strlcpy((char*)buf, "test\n", len);
}
ssize_t f_write(void *cookie, const void *buf, size_t len) {
assert(cookie == &cookie_var);
char *data = strndup((char*)buf, len);
assert(data);
printf("WRITE CALLED: %s\n", data);
free(data);
return len;
}
off_t f_seek(void *cookie, off_t off, int whence) {
assert(cookie == &cookie_var);
assert(whence == SEEK_SET);
printf("SEEK CALLED; off=%d, whence=%d\n", (int)off, whence);
return off;
}
int f_flush(void *cookie) {
assert(cookie == &cookie_var);
printf("FLUSH CALLED\n");
return 0;
}
int f_close(void *cookie) {
assert(cookie == &cookie_var);
printf("CLOSE CALLED\n");
return 0;
}
int main(void) {
FILE *fp;
char buf[10];
// 1. read-only variant
fp = fropen2(&cookie_var, f_read);
assert(fp);
// verify that fileno() does not crash or report nonsense
assert(fileno(fp) == -1);
assert(fgets(buf, sizeof(buf), fp));
printf("READ: %s", buf);
assert(!fclose(fp));
// 2. write-only variant
fp = fwopen2(&cookie_var, f_write);
assert(fp);
assert(fileno(fp) == -1);
assert(fputs("test", fp) >= 0);
assert(!fclose(fp));
// 3. read+write+close
fp = funopen2(&cookie_var, f_read, f_write, NULL, NULL, f_close);
assert(fp);
assert(fileno(fp) == -1);
assert(fgets(buf, sizeof(buf), fp));
printf("READ: %s", buf);
assert(fputs("test", fp) >= 0);
assert(!fflush(fp));
assert(!fclose(fp));
// 4. read+seek
fp = funopen2(&cookie_var, f_read, NULL, f_seek, NULL, NULL);
assert(fp);
assert(fileno(fp) == -1);
assert(fseek(fp, 100, SEEK_SET) == 0);
assert(fgets(buf, sizeof(buf), fp));
printf("READ: %s", buf);
assert(!fclose(fp));
// 5. write+flush
fp = funopen2(&cookie_var, NULL, f_write, NULL, f_flush, NULL);
assert(fp);
assert(fileno(fp) == -1);
assert(fputs("test", fp) >= 0);
assert(!fflush(fp));
assert(fputs("test", fp) >= 0);
// NB: fclose() also implicitly calls flush
assert(!fclose(fp));
return 0;
}
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