#include <fcntl.h> #include <sys/stat.h> #ifndef TST_FALLOCATE64 # define stat64 stat # define fstat64 fstat # else # ifndef O_LARGEFILE # error no O_LARGEFILE but you want to test with LFS enabled # endif #endif static void do_prepare(void); static int do_test(void); #define PREPARE(argc, argv) do_prepare () #define TEST_FUNCTION do_test () #include <test-skeleton.c> static int fd; static void do_prepare (void) { fd = create_temp_file ("tst-fallocate.", NULL); if (fd == -1) { printf ("cannot create temporary file: %m\n"); exit (1); } } static int do_test (void) { struct stat64 st; int c; char garbage[4096]; blkcnt_t blksb4; if (fstat64 (fd, &st) != 0) { puts ("1st fstat failed"); return 1; } if (st.st_size != 0) { puts ("file not created with size 0"); return 1; } /* This is the default mode which is identical to posix_fallocate(). Note: we need a few extra blocks for FALLOC_FL_PUNCH_HOLE below. While block sizes vary, we'll assume eight 4K blocks for good measure. */ if (fallocate (fd, 0, 8 * 4096, 128) != 0) { puts ("1st fallocate call failed"); return 1; } if (fstat64 (fd, &st) != 0) { puts ("2nd fstat failed"); return 1; } if (st.st_size != 8 * 4096 + 128) { printf ("file size after 1st fallocate call is %llu, expected %u\n", (unsigned long long int) st.st_size, 8u * 4096u + 128u); return 1; } /* Without FALLOC_FL_KEEP_SIZE, this would increaste the size of the file. */ if (fallocate (fd, FALLOC_FL_KEEP_SIZE, 0, 16 * 4096) != 0) { puts ("2nd fallocate call failed"); return 1; } if (fstat64 (fd, &st) != 0) { puts ("3rd fstat failed"); return 1; } if (st.st_size != 8 * 4096 + 128) { printf ("file size changed in 2nd fallocate call to %llu, expected %u\n", (unsigned long long int) st.st_size, 8u * 4096u + 128u); return 1; } /* Let's fill up the first eight 4k blocks with 'x' to force some allocations. */ memset(garbage, 'x', 4096); for(c=0; c < 8; c++) if(write(fd, garbage, 4096) == -1) { puts ("write failed"); return 1; } if (fstat64 (fd, &st) != 0) { puts ("4th fstat failed"); return 1; } blksb4 = st.st_blocks; /* Let's punch a hole in the entire file, turning it effectively into a sparse file. */ if (fallocate (fd, FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE, 0, 8 * 4096 + 128) != 0) { puts ("3rd fallocate call failed"); return 1; } if (fstat64 (fd, &st) != 0) { puts ("5th fstat failed"); return 1; } if (st.st_size != 8 * 4096 + 128) { printf ("file size after 3rd fallocate call is %llu, expected %u\n", (unsigned long long int) st.st_size, 8u * 4096u + 128u); return 1; } /* The number of allocated blocks should decrease. I hope this works on all filesystems! */ if (st.st_blocks >= blksb4) { printf ("number of blocks after 3rd fallocate call is %lu, expected less than %lu\n", (unsigned long int) st.st_blocks, blksb4); return 1; } #ifdef TST_FALLOCATE64 /* We'll just do a mode = 0 test for fallocate64() */ if (fallocate64 (fd, 0, 4097ULL, 4294967295ULL + 2ULL) != 0) { puts ("1st fallocate64 call failed"); return 1; } if (fstat64 (fd, &st) != 0) { puts ("6th fstat failed"); return 1; } if (st.st_size != 4097ULL + 4294967295ULL + 2ULL) { printf ("file size after 1st fallocate64 call is %llu, expected %llu\n", (unsigned long long int) st.st_size, 4097ULL + 4294967295ULL + 2ULL); return 1; } #endif close (fd); return 0; }