diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backup.c | 151 | ||||
| -rw-r--r-- | src/backup.h | 9 | ||||
| -rw-r--r-- | src/main.c | 287 | ||||
| -rw-r--r-- | src/resources.h | 2 | ||||
| -rw-r--r-- | src/restore.c | 150 | ||||
| -rw-r--r-- | src/restore.h | 9 |
6 files changed, 325 insertions, 283 deletions
diff --git a/src/backup.c b/src/backup.c new file mode 100644 index 0000000..b4c0e0a --- /dev/null +++ b/src/backup.c @@ -0,0 +1,151 @@ +#include "backup.h" + +#include "file.h" +#include "print.h" + +#include <errno.h> +#include <inttypes.h> +#include <stdlib.h> +#include <string.h> + +int +backup(const options_t *const opts, resources_t *const res) +{ + const long in_size = file_size(res->in_file); + + if (in_size < 0) { + print_error("cannot get size of input file: %s", strerror(errno)); + return 1; + } + + const long ref_size = file_size(res->ref_file); + + if (ref_size < 0) { + print_error("cannot get size of reference file: %s", strerror(errno)); + return 1; + } + + /* Check sizes of the input file and the reference file */ + if (in_size != ref_size) { + print_error("input file and reference file differ in size"); + return 1; + } else if ((in_size % opts->sector_size) != 0) { + print_error( + "size of input file and reference file is not multiple of" PRIu32, + opts->sector_size); + return 1; + } + + /* Allocate the buffers */ + /* The output buffer contains also the offsets */ + const size_t out_buffer_size = + ((opts->buffer_size / opts->sector_size) * sizeof(uint64_t)) + + opts->buffer_size; + + if ((res->in_buffer = (char *)malloc(opts->buffer_size)) == NULL) { + print_error("cannot allocate buffer for input file data"); + return 1; + } else if ((res->ref_buffer = (char *)malloc(opts->buffer_size)) == NULL) { + print_error("cannot allocate buffer for reference file data"); + return 1; + } else if ((res->out_buffer = (char *)malloc(out_buffer_size)) == NULL) { + print_error("cannot allocate buffer for output file data"); + return 1; + } + + size_t out_buffer_index = 0; + uint64_t offset = 0; + + for (;;) { + /* Read the sectors from the input file to the buffer */ + const size_t in_read = + fread(res->in_buffer, 1U, opts->buffer_size, res->in_file); + + if ((in_read % opts->sector_size) != 0) { + print_error( + "data read from input file is not multiple of sector size"); + return 1; + } else if (ferror(res->in_file)) { + print_error("cannot read from input file: %s", strerror(errno)); + return 1; + } + + /* Read sectors from the reference file to the buffer */ + const size_t ref_read = + fread(res->ref_buffer, 1U, opts->buffer_size, res->ref_file); + + if ((ref_read % opts->sector_size) != 0) { + print_error( + "data read from reference file is not multiple of sector size"); + return 1; + } else if (ferror(res->ref_file)) { + print_error("%s", strerror(errno)); + return 1; + } + + if (in_read != ref_read) { + print_error( + "data read from input file and reference file differ in size"); + return 1; + } + + /* Process sectors in the buffer */ + for (size_t i = 0; i < in_read; i += opts->sector_size) { + /* Compare the sectors */ + int changed = 0; + const size_t j_end = i + opts->sector_size; + for (size_t j = i; j < j_end; ++j) { + if (res->in_buffer[j] != res->ref_buffer[j]) { + changed = 1; + break; + } + } + + if (changed) { + /* Write changed sector */ + if (out_buffer_index >= out_buffer_size) { + /* The output buffer is full. Write it to the + * output file. + */ + const size_t x = fwrite(res->out_buffer, 1U, + out_buffer_index, res->out_file); + + if (x != out_buffer_index) { + print_error("cannot write to output file: %s", + strerror(errno)); + return 1; + } + + out_buffer_index = 0; + } + + const uint64_t o = htole64(offset); + + memcpy(res->out_buffer + out_buffer_index, (void *)&o, + sizeof(o)); + memcpy(res->out_buffer + out_buffer_index, &(res->in_buffer[i]), + opts->sector_size); + out_buffer_index += sizeof(o) + opts->sector_size; + } + + offset += opts->sector_size; + } + + if (feof(res->in_file)) { + break; + } + } + + /* Write out the output buffer */ + if (out_buffer_index >= 0) { + const size_t x = + fwrite(res->out_buffer, 1U, out_buffer_index, res->out_file); + + if (x != out_buffer_index) { + print_error("cannot write to output file: %s", strerror(errno)); + return 1; + } + } + + return 0; +} diff --git a/src/backup.h b/src/backup.h new file mode 100644 index 0000000..9d80b67 --- /dev/null +++ b/src/backup.h @@ -0,0 +1,9 @@ +#ifndef BACKUP_H +#define BACKUP_H + +#include "options.h" +#include "resources.h" + +int backup(const options_t *const opts, resources_t *const res); + +#endif /* BACKUP_H */ @@ -6,10 +6,12 @@ #include <stdlib.h> #include <string.h> +#include "backup.h" #include "file.h" #include "options.h" #include "print.h" #include "resources.h" +#include "restore.h" static void clean_exit(resources_t *const res, int exit_code) @@ -58,287 +60,6 @@ open_files(const options_t *const opts, resources_t *const res, return 0; } -static bool -is_reference_file_valid(resources_t *const res, uint32_t sector_size) -{ - const long ref_size = file_size(res->ref_file); - - if (ref_size < 0) { - print_error("cannot get size of reference file: %s", strerror(errno)); - return false; - } else if (ref_size == 0) { - print_error("reference file is empty"); - return false; - } else if ((ref_size % (sizeof(uint64_t) + sector_size)) != 0) { - /* The reference file must hold equally sized sectors and the - * offset of each of them - */ - print_error( - "reference file has size that cannot contain valid diff data"); - return false; - } - - const long out_size = file_size(res->out_file); - - if (out_size < 0) { - print_error("cannot get size of output file: %s", strerror(errno)); - return 1; - } - - uint64_t ref_offset = 0; - uint64_t prev_out_offset; - - /* Scan the reference file and check */ - for (;;) { - uint64_t out_offset; - /* Read the next offset */ - const size_t ref_read = - fread(&out_offset, sizeof(out_offset), 1U, res->ref_file); - out_offset = le64toh(out_offset); - - if (feof(res->ref_file)) { - break; - } else if ((ref_read != 1U) || ferror(res->ref_file)) { - print_error("cannot read from reference file: %s", strerror(errno)); - return false; - } else if (((ref_offset != 0) && (out_offset <= prev_out_offset)) || - ((out_offset + sector_size) > out_size)) { - /* The offset must be higher than the previous one and it - * must point into the file - */ - print_error("reference file is not valid"); - return false; - } else if (fseek(res->ref_file, sector_size, SEEK_CUR) != 0) { - print_error("cannot seek in reference file: %s", strerror(errno)); - return false; - } - - prev_out_offset = out_offset; - } - - if (ftell(res->ref_file) != ref_size) { - /* The reference file must be read completely */ - print_error("reference file is not valid"); - return false; - } else if (fseek(res->ref_file, 0L, SEEK_SET) != 0) { - /* The file must be prepared for the restoring */ - print_error("cannot seek in reference file: %s", strerror(errno)); - return false; - } - - return true; -} - -static int -diff_backup(const options_t *const opts, resources_t *const res) -{ - const long in_size = file_size(res->in_file); - - if (in_size < 0) { - print_error("cannot get size of input file: %s", strerror(errno)); - return 1; - } - - const long ref_size = file_size(res->ref_file); - - if (ref_size < 0) { - print_error("cannot get size of reference file: %s", strerror(errno)); - return 1; - } - - /* Check sizes of the input file and the reference file */ - if (in_size != ref_size) { - print_error("input file and reference file differ in size"); - return 1; - } else if ((in_size % opts->sector_size) != 0) { - print_error( - "size of input file and reference file is not multiple of" PRIu32, - opts->sector_size); - return 1; - } - - /* Allocate the buffers */ - /* The output buffer contains also the offsets */ - const size_t out_buffer_size = - ((opts->buffer_size / opts->sector_size) * sizeof(uint64_t)) + - opts->buffer_size; - - if ((res->in_buffer = (char *)malloc(opts->buffer_size)) == NULL) { - print_error("cannot allocate buffer for input file data"); - return 1; - } else if ((res->ref_buffer = (char *)malloc(opts->buffer_size)) == NULL) { - print_error("cannot allocate buffer for reference file data"); - return 1; - } else if ((res->out_buffer = (char *)malloc(out_buffer_size)) == NULL) { - print_error("cannot allocate buffer for output file data"); - return 1; - } - - size_t out_buffer_index = 0; - uint64_t offset = 0; - - for (;;) { - /* Read the sectors from the input file to the buffer */ - const size_t in_read = - fread(res->in_buffer, 1U, opts->buffer_size, res->in_file); - - if ((in_read % opts->sector_size) != 0) { - print_error( - "data read from input file is not multiple of sector size"); - return 1; - } else if (ferror(res->in_file)) { - print_error("cannot read from input file: %s", strerror(errno)); - return 1; - } - - /* Read sectors from the reference file to the buffer */ - const size_t ref_read = - fread(res->ref_buffer, 1U, opts->buffer_size, res->ref_file); - - if ((ref_read % opts->sector_size) != 0) { - print_error( - "data read from reference file is not multiple of sector size"); - return 1; - } else if (ferror(res->ref_file)) { - print_error("%s", strerror(errno)); - return 1; - } - - if (in_read != ref_read) { - print_error( - "data read from input file and reference file differ in size"); - return 1; - } - - /* Process sectors in the buffer */ - for (size_t i = 0; i < in_read; i += opts->sector_size) { - /* Compare the sectors */ - int changed = 0; - const size_t j_end = i + opts->sector_size; - for (size_t j = i; j < j_end; ++j) { - if (res->in_buffer[j] != res->ref_buffer[j]) { - changed = 1; - break; - } - } - - if (changed) { - /* Write changed sector */ - if (out_buffer_index >= out_buffer_size) { - /* The output buffer is full. Write it to the - * output file. - */ - const size_t x = fwrite(res->out_buffer, 1U, - out_buffer_index, res->out_file); - - if (x != out_buffer_index) { - print_error("cannot write to output file: %s", - strerror(errno)); - return 1; - } - - out_buffer_index = 0; - } - - const uint64_t o = htole64(offset); - - memcpy(res->out_buffer + out_buffer_index, (void *)&o, - sizeof(o)); - memcpy(res->out_buffer + out_buffer_index, &(res->in_buffer[i]), - opts->sector_size); - out_buffer_index += sizeof(o) + opts->sector_size; - } - - offset += opts->sector_size; - } - - if (feof(res->in_file)) { - break; - } - } - - /* Write out the output buffer */ - if (out_buffer_index >= 0) { - const size_t x = - fwrite(res->out_buffer, 1U, out_buffer_index, res->out_file); - - if (x != out_buffer_index) { - print_error("cannot write to output file: %s", strerror(errno)); - return 1; - } - } - - return 0; -} - -static int -diff_restore(const options_t *const opts, resources_t *const res) -{ - /* Check validity of the reference file */ - if (!is_reference_file_valid(res, opts->sector_size)) { - return 1; - } - - const long ref_size = file_size(res->ref_file); - - if (ref_size < 0) { - print_error("cannot get size of reference file: %s", strerror(errno)); - return 1; - } - - /* Allocate the buffer for data from the reference file */ - /* The reference buffer contains also the offsets */ - const size_t ref_buffer_size = - ((opts->buffer_size / opts->sector_size) * sizeof(uint64_t)) + - opts->buffer_size; - - if ((res->ref_buffer = (char *)malloc(ref_buffer_size)) == NULL) { - print_error("cannot allocate buffer for reference file data"); - return 1; - } - - /* Restore data from the differential image */ - uint64_t out_offset; - - for (;;) { - /* Read data of the offset and the next sector */ - const size_t ref_read = - fread(res->ref_buffer, ref_buffer_size, 1U, res->ref_file); - - if (feof(res->ref_file)) { - break; - } else if ((ref_read != 1U) || ferror(res->ref_file)) { - print_error("cannot read from reference file: %s", strerror(errno)); - return 1; - } - - /* Get offset */ - out_offset = le64toh(*((uint64_t *)res->ref_buffer)); - - if (fseek(res->out_file, out_offset, SEEK_SET) != 0) { - print_error("cannot seek in output file: %s", strerror(errno)); - return 1; - } - - /* Write the sector data to the output file */ - const size_t out_written = fwrite(res->ref_buffer + sizeof(out_offset), - opts->sector_size, 1U, res->out_file); - - if (out_written != 1U) { - print_error("cannot write to output file: %s", strerror(errno)); - return 1; - } - } - - /* The reference file must be read completely */ - if (ftell(res->ref_file) != ref_size) { - print_error("reference file is not valid"); - return 1; - } - - return 0; -} - int main(int argc, char **argv) { @@ -356,8 +77,8 @@ main(int argc, char **argv) if (open_files(&opts, &res, is_action_backup) != 0) { clean_exit(&res, 1); } else if (is_action_backup) { - clean_exit(&res, diff_backup(&opts, &res)); + clean_exit(&res, backup(&opts, &res)); } else { - clean_exit(&res, diff_restore(&opts, &res)); + clean_exit(&res, restore(&opts, &res)); } } diff --git a/src/resources.h b/src/resources.h index 0cf9777..8effb0c 100644 --- a/src/resources.h +++ b/src/resources.h @@ -1,6 +1,8 @@ #ifndef RESOURCES_H #define RESOURCES_H +#include <stdio.h> + typedef struct { FILE *in_file; FILE *ref_file; diff --git a/src/restore.c b/src/restore.c new file mode 100644 index 0000000..c6121c1 --- /dev/null +++ b/src/restore.c @@ -0,0 +1,150 @@ +#include "restore.h" + +#include "file.h" +#include "print.h" + +#include <errno.h> +#include <stdbool.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +static bool +is_reference_file_valid(resources_t *const res, uint32_t sector_size) +{ + const long ref_size = file_size(res->ref_file); + + if (ref_size < 0) { + print_error("cannot get size of reference file: %s", strerror(errno)); + return false; + } else if (ref_size == 0) { + print_error("reference file is empty"); + return false; + } else if ((ref_size % (sizeof(uint64_t) + sector_size)) != 0) { + /* The reference file must hold equally sized sectors and the + * offset of each of them + */ + print_error( + "reference file has size that cannot contain valid diff data"); + return false; + } + + const long out_size = file_size(res->out_file); + + if (out_size < 0) { + print_error("cannot get size of output file: %s", strerror(errno)); + return 1; + } + + uint64_t ref_offset = 0; + uint64_t prev_out_offset; + + /* Scan the reference file and check */ + for (;;) { + uint64_t out_offset; + /* Read the next offset */ + const size_t ref_read = + fread(&out_offset, sizeof(out_offset), 1U, res->ref_file); + out_offset = le64toh(out_offset); + + if (feof(res->ref_file)) { + break; + } else if ((ref_read != 1U) || ferror(res->ref_file)) { + print_error("cannot read from reference file: %s", strerror(errno)); + return false; + } else if (((ref_offset != 0) && (out_offset <= prev_out_offset)) || + ((out_offset + sector_size) > out_size)) { + /* The offset must be higher than the previous one and it + * must point into the file + */ + print_error("reference file is not valid"); + return false; + } else if (fseek(res->ref_file, sector_size, SEEK_CUR) != 0) { + print_error("cannot seek in reference file: %s", strerror(errno)); + return false; + } + + prev_out_offset = out_offset; + } + + if (ftell(res->ref_file) != ref_size) { + /* The reference file must be read completely */ + print_error("reference file is not valid"); + return false; + } else if (fseek(res->ref_file, 0L, SEEK_SET) != 0) { + /* The file must be prepared for the restoring */ + print_error("cannot seek in reference file: %s", strerror(errno)); + return false; + } + + return true; +} + +int +restore(const options_t *const opts, resources_t *const res) +{ + /* Check validity of the reference file */ + if (!is_reference_file_valid(res, opts->sector_size)) { + return 1; + } + + const long ref_size = file_size(res->ref_file); + + if (ref_size < 0) { + print_error("cannot get size of reference file: %s", strerror(errno)); + return 1; + } + + /* Allocate the buffer for data from the reference file */ + /* The reference buffer contains also the offsets */ + const size_t ref_buffer_size = + ((opts->buffer_size / opts->sector_size) * sizeof(uint64_t)) + + opts->buffer_size; + + if ((res->ref_buffer = (char *)malloc(ref_buffer_size)) == NULL) { + print_error("cannot allocate buffer for reference file data"); + return 1; + } + + /* Restore data from the differential image */ + uint64_t out_offset; + + for (;;) { + /* Read data of the offset and the next sector */ + const size_t ref_read = + fread(res->ref_buffer, ref_buffer_size, 1U, res->ref_file); + + if (feof(res->ref_file)) { + break; + } else if ((ref_read != 1U) || ferror(res->ref_file)) { + print_error("cannot read from reference file: %s", strerror(errno)); + return 1; + } + + /* Get offset */ + out_offset = le64toh(*((uint64_t *)res->ref_buffer)); + + if (fseek(res->out_file, out_offset, SEEK_SET) != 0) { + print_error("cannot seek in output file: %s", strerror(errno)); + return 1; + } + + /* Write the sector data to the output file */ + const size_t out_written = fwrite(res->ref_buffer + sizeof(out_offset), + opts->sector_size, 1U, res->out_file); + + if (out_written != 1U) { + print_error("cannot write to output file: %s", strerror(errno)); + return 1; + } + } + + /* The reference file must be read completely */ + if (ftell(res->ref_file) != ref_size) { + print_error("reference file is not valid"); + return 1; + } + + return 0; +} diff --git a/src/restore.h b/src/restore.h new file mode 100644 index 0000000..cc095b9 --- /dev/null +++ b/src/restore.h @@ -0,0 +1,9 @@ +#ifndef RESTORE_H +#define RESTORE_H + +#include "options.h" +#include "resources.h" + +int restore(const options_t *const opts, resources_t *const res); + +#endif /* RESTORE_H */ |