From 54ac0dd3086d2ab4f153c08811da229a23916c68 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Thu, 4 May 2017 13:25:05 -0500 Subject: [PATCH] punch-alternating: add some options I didn't end up using this, but somebody else might find it useful, so sending it. This change lets us specify punch patterns other than literally every other block. i.e. punch-alternating with no options will do: ...HDHDHDHDHDHD... -i 4 -s 2 will do: ...DDHHDDHHDDHH... or -i 3 -s 1 will do: ...DDHDDHDDHDDH... [eguan: don't allow 0 size and fixed perror string] Signed-off-by: Eric Sandeen Reviewed-by: Eryu Guan Signed-off-by: Eryu Guan --- src/punch-alternating.c | 47 ++++++++++++++++++++++++++++++++++------- 1 file changed, 39 insertions(+), 8 deletions(-) diff --git a/src/punch-alternating.c b/src/punch-alternating.c index 4148622f..25228cd5 100644 --- a/src/punch-alternating.c +++ b/src/punch-alternating.c @@ -11,6 +11,14 @@ #include #include "global.h" +void usage(char *cmd) +{ + printf("Usage: %s [-i interval] [-s size] file\n", cmd); + printf("Punches every other block in the file by default,\n"); + printf("or 'size' blocks every 'interval' blocks with options.\n"); + exit(1); +} + int main(int argc, char *argv[]) { struct stat s; @@ -21,14 +29,37 @@ int main(int argc, char *argv[]) off_t sz; int mode; int error; + int c; + int size = 1; /* punch $SIZE blocks ... */ + int interval = 2; /* every $INTERVAL blocks */ + + while ((c = getopt(argc, argv, "i:s:")) != EOF) { + switch (c) { + case 'i': + interval = atoi(optarg); + break; + case 's': + size = atoi(optarg); + break; + default: + usage(argv[0]); + } + } + + if (interval <= 0) { + printf("interval must be > 0\n"); + usage(argv[0]); + } - if (argc != 2) { - printf("Usage: %s file\n", argv[0]); - printf("Punches every other block in the file.\n"); - return 1; + if (size <= 0) { + printf("size must be > 0\n"); + usage(argv[0]); } - fd = open(argv[1], O_WRONLY); + if (optind != argc - 1) + usage(argv[0]); + + fd = open(argv[optind], O_WRONLY); if (fd < 0) goto err; @@ -44,8 +75,8 @@ int main(int argc, char *argv[]) blksz = sf.f_bsize; mode = FALLOC_FL_PUNCH_HOLE | FALLOC_FL_KEEP_SIZE; - for (offset = 0; offset < sz; offset += blksz * 2) { - error = fallocate(fd, mode, offset, blksz); + for (offset = 0; offset < sz; offset += blksz * interval) { + error = fallocate(fd, mode, offset, blksz * size); if (error) goto err; } @@ -59,6 +90,6 @@ int main(int argc, char *argv[]) goto err; return 0; err: - perror(argv[1]); + perror(argv[optind]); return 2; } -- 2.30.2