From 007dcec23ece3dd66cd6079e43e6f0b44e7da80b Mon Sep 17 00:00:00 2001 From: Raghavendra Bhat Date: Fri, 24 Feb 2012 12:53:39 +0530 Subject: sparse: add sparse file creation tools to the git sparse_file_write.c: This program takes the filename and the size as the argument from the user (default size 5GB) and creates the sparse file with the name and the size provided. sparse_file_alt.c: This program will create a sparse file with alternate empty blocks and data blocks. Takes the path as the argument Change-Id: I8dfc95c933167fefc53fb0b665f234997aa0c68f Signed-off-by: Raghavendra Bhat --- c_pgms/sparse/sparse_file_alt.c | 46 ++++++++++++ c_pgms/sparse/sparse_file_write.c | 151 ++++++++++++++++++++++++++++++++++++++ 2 files changed, 197 insertions(+) create mode 100644 c_pgms/sparse/sparse_file_alt.c create mode 100644 c_pgms/sparse/sparse_file_write.c diff --git a/c_pgms/sparse/sparse_file_alt.c b/c_pgms/sparse/sparse_file_alt.c new file mode 100644 index 0000000..4afaa37 --- /dev/null +++ b/c_pgms/sparse/sparse_file_alt.c @@ -0,0 +1,46 @@ +#include +#include +#include +#include +#include +#include +#include + +#define BLOCK_SIZE 4096 + +void *buf; + +int main(int argc, char **argv) +{ + buf = malloc (512); + memset (buf,"a",512); + int fd = 0; + int i; + int sector_per_block = BLOCK_SIZE/512; + int block_count = 4; + + if(argc != 2) { + printf ("Wrong usage\n USAGE: program absolute_path_to_write\n"); + _exit (-1); + } + + fd = open (argv[1],O_RDWR | O_CREAT,0666); + if (fd <= 0) { + printf ("file open failed\n"); + _exit (0); + } + + while (block_count > 0) { + lseek (fd, BLOCK_SIZE, SEEK_CUR); + block_count--; + + for(i = 0; i < sector_per_block; i++) + write (fd, buf, 512); + + block_count--; + } + + close(fd); + + return 0; +} diff --git a/c_pgms/sparse/sparse_file_write.c b/c_pgms/sparse/sparse_file_write.c new file mode 100644 index 0000000..cc95027 --- /dev/null +++ b/c_pgms/sparse/sparse_file_write.c @@ -0,0 +1,151 @@ +#include +#include +#include +#include +#include +#include +#include +#include + +#define UNIT_KB 1024ULL +#define UNIT_MB UNIT_KB*1024ULL +#define UNIT_GB UNIT_MB*1024ULL +#define UNIT_TB UNIT_GB*1024ULL +#define UNIT_PB UNIT_TB*1024ULL + +#define UNIT_KB_STRING "KB" +#define UNIT_MB_STRING "MB" +#define UNIT_GB_STRING "GB" +#define UNIT_TB_STRING "TB" +#define UNIT_PB_STRING "PB" + +int +string2bytesize (const char *str, unsigned long long *n) +{ + unsigned long long value = 0ULL; + char *tail = NULL; + int old_errno = 0; + const char *s = NULL; + + if (str == NULL || n == NULL) + { + errno = EINVAL; + return -1; + } + + for (s = str; *s != '\0'; s++) + { + if (isspace (*s)) + { + continue; + } + if (*s == '-') + { + return -1; + } + break; + } + + old_errno = errno; + errno = 0; + value = strtoull (str, &tail, 10); + + if (errno == ERANGE || errno == EINVAL) + { + return -1; + } + + if (errno == 0) + { + errno = old_errno; + } + + if (tail[0] != '\0') + { + if (strcasecmp (tail, UNIT_KB_STRING) == 0) + { + value *= UNIT_KB; + } + else if (strcasecmp (tail, UNIT_MB_STRING) == 0) + { + value *= UNIT_MB; + } + else if (strcasecmp (tail, UNIT_GB_STRING) == 0) + { + value *= UNIT_GB; + } + else if (strcasecmp (tail, UNIT_TB_STRING) == 0) + { + value *= UNIT_TB; + } + else if (strcasecmp (tail, UNIT_PB_STRING) == 0) + { + value *= UNIT_PB; + } + + else + { + return -1; + } + } + + *n = value; + + return 0; +} + +int main (int argc, char *argv[]) +{ + int ret = -1; + int fd = -1; + char *buf = "This is a string"; + char *filename = NULL; + unsigned long long size = 0; + + if (argc < 2) { + fprintf (stderr, "Usage:./a.out \n"); + return 2; + } + + filename = argv[1]; + + fd = open (filename, O_CREAT|O_RDWR, 0644); + if (fd == -1) { + fprintf (stderr, "OPEN: cannot open the file fff. (%s)", + strerror (errno)); + return 2; + } + + if (argc < 3) + size = 5 * UNIT_GB; + else + string2bytesize (argv[2], &size); + + ret = ftruncate (fd, size); + if (ret == -1) { + fprintf (stderr, "TRUNCATE: cannot truncate the file %s. (%s)", + filename, strerror (errno)); + goto out; + } + + ret = lseek (fd, 1048576, SEEK_SET); + if (ret == -1) { + fprintf (stderr, "LSEEK: cannot seek to the offset file fff. " + "(%s)", strerror (errno)); + goto out; + } + + ret = write (fd, buf, strlen (buf)); + if (ret == -1) { + fprintf (stderr, "WRITE: cannot write to the file fff. (%s)", + strerror (errno)); + goto out; + } + + ret = 0; +out: + if (fd) + close (fd); + + return ret; +} -- cgit