From 02ffe0ed4113e7b479197d0ba1b160e6280b4099 Mon Sep 17 00:00:00 2001 From: Jan Sucan Date: Sun, 2 May 2021 10:19:23 +0200 Subject: Move the source files to a src directory --- .gitignore | 4 +- Makefile | 21 +--- file.c | 23 ---- file.h | 8 -- main.c | 376 -------------------------------------------------------- options.c | 118 ------------------ options.h | 19 --- print.c | 21 ---- print.h | 6 - resources.c | 44 ------- resources.h | 17 --- src/Makefile | 19 +++ src/file.c | 23 ++++ src/file.h | 8 ++ src/main.c | 376 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ src/options.c | 118 ++++++++++++++++++ src/options.h | 19 +++ src/print.c | 21 ++++ src/print.h | 6 + src/resources.c | 44 +++++++ src/resources.h | 17 +++ tests/Makefile | 2 +- 22 files changed, 659 insertions(+), 651 deletions(-) delete mode 100644 file.c delete mode 100644 file.h delete mode 100644 main.c delete mode 100644 options.c delete mode 100644 options.h delete mode 100644 print.c delete mode 100644 print.h delete mode 100644 resources.c delete mode 100644 resources.h create mode 100644 src/Makefile create mode 100644 src/file.c create mode 100644 src/file.h create mode 100644 src/main.c create mode 100644 src/options.c create mode 100644 src/options.h create mode 100644 src/print.c create mode 100644 src/print.h create mode 100644 src/resources.c create mode 100644 src/resources.h diff --git a/.gitignore b/.gitignore index 13e7c1a..3dc9774 100644 --- a/.gitignore +++ b/.gitignore @@ -1,3 +1,3 @@ *~ -diff-dd -program_info.h +src/diff-dd +src/program_info.h diff --git a/Makefile b/Makefile index 04b5c90..dcd38c3 100644 --- a/Makefile +++ b/Makefile @@ -1,22 +1,11 @@ PROGRAM_NAME=diff-dd PROGRAM_VERSION=1.0 -# Program name is used in the tests to locate the executable file -export PROGRAM_NAME - -CC=gcc -CFLAGS=-Wall - -SOURCES=*.c -HEADERS=*.h -all: $(PROGRAM_NAME) - -$(PROGRAM_NAME): $(SOURCES) $(HEADERS) program_info.h - $(CC) $(CFLAGS) -o $(PROGRAM_NAME) $(SOURCES) +export PROGRAM_NAME +export PROGRAM_VERSION -program_info.h: - echo "#define PROGRAM_NAME_STR \"$(PROGRAM_NAME)\"" >program_info.h - echo "#define PROGRAM_VERSION_STR \"$(PROGRAM_VERSION)\"" >>program_info.h +all: + $(MAKE) -C src all .PHONY: test clean @@ -24,4 +13,4 @@ test: all $(MAKE) -C tests clean: - rm -f *.o *~ $(PROGRAM_NAME) program_info.h + $(MAKE) -C src clean diff --git a/file.c b/file.c deleted file mode 100644 index c6823b9..0000000 --- a/file.c +++ /dev/null @@ -1,23 +0,0 @@ -#include -#include - -#include "file.h" -#include "print.h" - -long -file_size(FILE *const file) -{ - fpos_t p; - - if ((fgetpos(file, &p) != 0) || (fseek(file, 0L, SEEK_END) != 0)) { - return -1; - } - - const long size = ftell(file); - - if (fsetpos(file, &p) != 0) { - return -1; - } - - return size; -} diff --git a/file.h b/file.h deleted file mode 100644 index d62b1ba..0000000 --- a/file.h +++ /dev/null @@ -1,8 +0,0 @@ -#ifndef FILE_H -#define FILE_H - -#include - -long file_size(FILE *const file); - -#endif /* FILE_H */ diff --git a/main.c b/main.c deleted file mode 100644 index ea94921..0000000 --- a/main.c +++ /dev/null @@ -1,376 +0,0 @@ -#include -#include -#include -#include -#include -#include -#include - -#include "file.h" -#include "options.h" -#include "print.h" -#include "resources.h" - -/* This header file is automatically generated at build time from the Makefile - */ -#include "program_info.h" - -void -usage(int exit_code) -{ - printf("Usage: %s [-s SECTOR_SIZE] [-b BUFFER_SIZE] [INFILE] REFFILE " - "OUTFILE\n", - PROGRAM_NAME_STR); - exit(exit_code); -} - -void -clean_exit(resources_t *const res, int exit_code) -{ - resources_free(res); - exit(exit_code); -} - -int -open_files(const options_t *const opts, resources_t *const res, - bool is_action_backup) -{ - /* Open the input file */ - if ((opts->in_file_path != NULL) && - ((res->in_file = fopen(opts->in_file_path, "r")) == NULL)) { - print_error("cannot open input file: %s", strerror(errno)); - return 1; - } - - /* Open the reference file */ - if ((res->ref_file = fopen(opts->ref_file_path, "r")) == NULL) { - print_error("cannot open reference file: %s", strerror(errno)); - return 1; - } - - /* Open the output file - * - * When restoring, the file must be opened for writing and not - * truncated - */ - char out_mode[] = "r+"; - - if (is_action_backup) { - /* When backing up, the output file is truncated to hold the - * new data - */ - out_mode[0] = 'w'; - out_mode[1] = '\0'; - } - - if ((res->out_file = fopen(opts->out_file_path, out_mode)) == NULL) { - print_error("cannot open output file: %s", strerror(errno)); - return 1; - } - - return 0; -} - -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 -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; -} - -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) -{ - options_t opts; - - if (options_parse(argc, argv, &opts) || opts.help) { - usage(1); - } - - const bool is_action_backup = (opts.in_file_path != NULL); - resources_t res; - - resources_init(&res); - - 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)); - } else { - clean_exit(&res, diff_restore(&opts, &res)); - } -} diff --git a/options.c b/options.c deleted file mode 100644 index 2017ba5..0000000 --- a/options.c +++ /dev/null @@ -1,118 +0,0 @@ -#include -#include -#include -#include -#include - -#include "options.h" -#include "print.h" - -#define OPTIONS_DEFAULT_SECTOR_SIZE 512 -#define OPTIONS_DEFAULT_BUFFER_SIZE (4 * 1024 * 1024) - -void options_init(options_t *const opts); -int options_parse_unsigned(const char *const arg, uint32_t *const value); - -int -options_parse(int argc, char **argv, options_t *const opts) -{ - options_init(opts); - - int ch; - char *arg_sector_size = NULL; - char *arg_buffer_size = NULL; - - while ((ch = getopt(argc, argv, ":s:b:h")) != -1) { - switch (ch) { - case 's': - arg_sector_size = optarg; - break; - - case 'b': - arg_buffer_size = optarg; - break; - - case 'h': - opts->help = true; - break; - - case ':': - print_error("missing argument for option '-%c'", optopt); - return 1; - - default: - print_error("unknown option '-%c'", optopt); - return 1; - } - } - - argc -= optind; - argv += optind; - - if (opts->help) { - return 0; - } else if (argc < 2) { - print_error("missing arguments"); - return 1; - } else if (argc > 3) { - print_error("too many arguments"); - return 1; - } - - /* Convert numbers in the arguments */ - if ((arg_sector_size != NULL) && - options_parse_unsigned(arg_sector_size, &(opts->sector_size))) { - print_error("incorrect sector size"); - return 1; - } else if ((arg_buffer_size != NULL) && - options_parse_unsigned(arg_buffer_size, &(opts->buffer_size))) { - print_error("incorrect buffer size"); - return 1; - } else if (opts->sector_size == 0) { - print_error("sector size cannot be 0"); - return 1; - } else if (opts->buffer_size == 0) { - print_error("buffer size cannot be 0"); - return 1; - } else if (opts->sector_size > opts->buffer_size) { - print_error("sector size cannot larger than buffer size"); - return 1; - } else if ((opts->buffer_size % opts->sector_size) != 0) { - print_error("buffer size is not multiple of sector size"); - return 1; - } - - /* Pick the file paths */ - int last_path_index = argc - 1; - opts->out_file_path = argv[last_path_index--]; - opts->ref_file_path = argv[last_path_index--]; - if (last_path_index >= 0) { - opts->in_file_path = argv[last_path_index]; - } - - return 0; -} - -void -options_init(options_t *const opts) -{ - opts->help = false; - opts->sector_size = OPTIONS_DEFAULT_SECTOR_SIZE; - opts->buffer_size = OPTIONS_DEFAULT_BUFFER_SIZE; - - opts->in_file_path = NULL; - opts->ref_file_path = NULL; - opts->out_file_path = NULL; -} - -int -options_parse_unsigned(const char *const arg, uint32_t *const value) -{ - char *end; - - errno = 0; - - *value = strtoul(arg, &end, 0); - - return ((*end != '\0') || (errno != 0)) ? -1 : 0; -} diff --git a/options.h b/options.h deleted file mode 100644 index 71259aa..0000000 --- a/options.h +++ /dev/null @@ -1,19 +0,0 @@ -#ifndef OPTIONS_H -#define OPTIONS_H - -#include -#include - -typedef struct { - bool help; - uint32_t sector_size; - uint32_t buffer_size; - - const char *in_file_path; - const char *ref_file_path; - const char *out_file_path; -} options_t; - -int options_parse(int argc, char **argv, options_t *const opts); - -#endif /* OPTIONS_H */ diff --git a/print.c b/print.c deleted file mode 100644 index 824f818..0000000 --- a/print.c +++ /dev/null @@ -1,21 +0,0 @@ -#include -#include - -#include "print.h" - -#define PRINT_ERROR_PREFIX "ERROR: " -#define PRINT_ERROR_SUFFIX "\n" - -void -print_error(const char *const format, ...) -{ - fprintf(stderr, PRINT_ERROR_PREFIX); - - va_list args; - - va_start(args, format); - vfprintf(stderr, format, args); - va_end(args); - - fprintf(stderr, PRINT_ERROR_SUFFIX); -} diff --git a/print.h b/print.h deleted file mode 100644 index 7992087..0000000 --- a/print.h +++ /dev/null @@ -1,6 +0,0 @@ -#ifndef PRINT_H -#define PRINT_H - -void print_error(const char *const format, ...); - -#endif /* PRINT_H */ diff --git a/resources.c b/resources.c deleted file mode 100644 index 3eebd1c..0000000 --- a/resources.c +++ /dev/null @@ -1,44 +0,0 @@ -#include -#include - -#include "resources.h" - -void -resources_init(resources_t *const res) -{ - res->in_file = NULL; - res->ref_file = NULL; - res->out_file = NULL; - res->in_buffer = NULL; - res->ref_buffer = NULL; - res->out_buffer = NULL; -} - -void -resources_free(resources_t *const res) -{ - if (res->in_file != NULL) { - fclose(res->in_file); - res->in_file = NULL; - } - if (res->ref_file != NULL) { - fclose(res->ref_file); - res->ref_file = NULL; - } - if (res->out_file != NULL) { - fclose(res->out_file); - res->out_file = NULL; - } - if (res->in_buffer != NULL) { - free(res->in_buffer); - res->in_buffer = NULL; - } - if (res->ref_buffer != NULL) { - free(res->ref_buffer); - res->ref_buffer = NULL; - } - if (res->out_buffer != NULL) { - free(res->out_buffer); - res->out_buffer = NULL; - } -} diff --git a/resources.h b/resources.h deleted file mode 100644 index 0cf9777..0000000 --- a/resources.h +++ /dev/null @@ -1,17 +0,0 @@ -#ifndef RESOURCES_H -#define RESOURCES_H - -typedef struct { - FILE *in_file; - FILE *ref_file; - FILE *out_file; - - char *in_buffer; - char *ref_buffer; - char *out_buffer; -} resources_t; - -void resources_init(resources_t *const res); -void resources_free(resources_t *const res); - -#endif /* RESOURCES_H */ diff --git a/src/Makefile b/src/Makefile new file mode 100644 index 0000000..8b24b35 --- /dev/null +++ b/src/Makefile @@ -0,0 +1,19 @@ +CC=gcc +CFLAGS=-Wall + +SOURCES=*.c +HEADERS=*.h + +all: $(PROGRAM_NAME) + +$(PROGRAM_NAME): $(SOURCES) $(HEADERS) program_info.h + $(CC) $(CFLAGS) -o $(PROGRAM_NAME) $(SOURCES) + +program_info.h: + echo "#define PROGRAM_NAME_STR \"$(PROGRAM_NAME)\"" >program_info.h + echo "#define PROGRAM_VERSION_STR \"$(PROGRAM_VERSION)\"" >>program_info.h + +.PHONY: clean + +clean: + rm -f *.o *~ $(PROGRAM_NAME) program_info.h diff --git a/src/file.c b/src/file.c new file mode 100644 index 0000000..c6823b9 --- /dev/null +++ b/src/file.c @@ -0,0 +1,23 @@ +#include +#include + +#include "file.h" +#include "print.h" + +long +file_size(FILE *const file) +{ + fpos_t p; + + if ((fgetpos(file, &p) != 0) || (fseek(file, 0L, SEEK_END) != 0)) { + return -1; + } + + const long size = ftell(file); + + if (fsetpos(file, &p) != 0) { + return -1; + } + + return size; +} diff --git a/src/file.h b/src/file.h new file mode 100644 index 0000000..d62b1ba --- /dev/null +++ b/src/file.h @@ -0,0 +1,8 @@ +#ifndef FILE_H +#define FILE_H + +#include + +long file_size(FILE *const file); + +#endif /* FILE_H */ diff --git a/src/main.c b/src/main.c new file mode 100644 index 0000000..ea94921 --- /dev/null +++ b/src/main.c @@ -0,0 +1,376 @@ +#include +#include +#include +#include +#include +#include +#include + +#include "file.h" +#include "options.h" +#include "print.h" +#include "resources.h" + +/* This header file is automatically generated at build time from the Makefile + */ +#include "program_info.h" + +void +usage(int exit_code) +{ + printf("Usage: %s [-s SECTOR_SIZE] [-b BUFFER_SIZE] [INFILE] REFFILE " + "OUTFILE\n", + PROGRAM_NAME_STR); + exit(exit_code); +} + +void +clean_exit(resources_t *const res, int exit_code) +{ + resources_free(res); + exit(exit_code); +} + +int +open_files(const options_t *const opts, resources_t *const res, + bool is_action_backup) +{ + /* Open the input file */ + if ((opts->in_file_path != NULL) && + ((res->in_file = fopen(opts->in_file_path, "r")) == NULL)) { + print_error("cannot open input file: %s", strerror(errno)); + return 1; + } + + /* Open the reference file */ + if ((res->ref_file = fopen(opts->ref_file_path, "r")) == NULL) { + print_error("cannot open reference file: %s", strerror(errno)); + return 1; + } + + /* Open the output file + * + * When restoring, the file must be opened for writing and not + * truncated + */ + char out_mode[] = "r+"; + + if (is_action_backup) { + /* When backing up, the output file is truncated to hold the + * new data + */ + out_mode[0] = 'w'; + out_mode[1] = '\0'; + } + + if ((res->out_file = fopen(opts->out_file_path, out_mode)) == NULL) { + print_error("cannot open output file: %s", strerror(errno)); + return 1; + } + + return 0; +} + +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 +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; +} + +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) +{ + options_t opts; + + if (options_parse(argc, argv, &opts) || opts.help) { + usage(1); + } + + const bool is_action_backup = (opts.in_file_path != NULL); + resources_t res; + + resources_init(&res); + + 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)); + } else { + clean_exit(&res, diff_restore(&opts, &res)); + } +} diff --git a/src/options.c b/src/options.c new file mode 100644 index 0000000..2017ba5 --- /dev/null +++ b/src/options.c @@ -0,0 +1,118 @@ +#include +#include +#include +#include +#include + +#include "options.h" +#include "print.h" + +#define OPTIONS_DEFAULT_SECTOR_SIZE 512 +#define OPTIONS_DEFAULT_BUFFER_SIZE (4 * 1024 * 1024) + +void options_init(options_t *const opts); +int options_parse_unsigned(const char *const arg, uint32_t *const value); + +int +options_parse(int argc, char **argv, options_t *const opts) +{ + options_init(opts); + + int ch; + char *arg_sector_size = NULL; + char *arg_buffer_size = NULL; + + while ((ch = getopt(argc, argv, ":s:b:h")) != -1) { + switch (ch) { + case 's': + arg_sector_size = optarg; + break; + + case 'b': + arg_buffer_size = optarg; + break; + + case 'h': + opts->help = true; + break; + + case ':': + print_error("missing argument for option '-%c'", optopt); + return 1; + + default: + print_error("unknown option '-%c'", optopt); + return 1; + } + } + + argc -= optind; + argv += optind; + + if (opts->help) { + return 0; + } else if (argc < 2) { + print_error("missing arguments"); + return 1; + } else if (argc > 3) { + print_error("too many arguments"); + return 1; + } + + /* Convert numbers in the arguments */ + if ((arg_sector_size != NULL) && + options_parse_unsigned(arg_sector_size, &(opts->sector_size))) { + print_error("incorrect sector size"); + return 1; + } else if ((arg_buffer_size != NULL) && + options_parse_unsigned(arg_buffer_size, &(opts->buffer_size))) { + print_error("incorrect buffer size"); + return 1; + } else if (opts->sector_size == 0) { + print_error("sector size cannot be 0"); + return 1; + } else if (opts->buffer_size == 0) { + print_error("buffer size cannot be 0"); + return 1; + } else if (opts->sector_size > opts->buffer_size) { + print_error("sector size cannot larger than buffer size"); + return 1; + } else if ((opts->buffer_size % opts->sector_size) != 0) { + print_error("buffer size is not multiple of sector size"); + return 1; + } + + /* Pick the file paths */ + int last_path_index = argc - 1; + opts->out_file_path = argv[last_path_index--]; + opts->ref_file_path = argv[last_path_index--]; + if (last_path_index >= 0) { + opts->in_file_path = argv[last_path_index]; + } + + return 0; +} + +void +options_init(options_t *const opts) +{ + opts->help = false; + opts->sector_size = OPTIONS_DEFAULT_SECTOR_SIZE; + opts->buffer_size = OPTIONS_DEFAULT_BUFFER_SIZE; + + opts->in_file_path = NULL; + opts->ref_file_path = NULL; + opts->out_file_path = NULL; +} + +int +options_parse_unsigned(const char *const arg, uint32_t *const value) +{ + char *end; + + errno = 0; + + *value = strtoul(arg, &end, 0); + + return ((*end != '\0') || (errno != 0)) ? -1 : 0; +} diff --git a/src/options.h b/src/options.h new file mode 100644 index 0000000..71259aa --- /dev/null +++ b/src/options.h @@ -0,0 +1,19 @@ +#ifndef OPTIONS_H +#define OPTIONS_H + +#include +#include + +typedef struct { + bool help; + uint32_t sector_size; + uint32_t buffer_size; + + const char *in_file_path; + const char *ref_file_path; + const char *out_file_path; +} options_t; + +int options_parse(int argc, char **argv, options_t *const opts); + +#endif /* OPTIONS_H */ diff --git a/src/print.c b/src/print.c new file mode 100644 index 0000000..824f818 --- /dev/null +++ b/src/print.c @@ -0,0 +1,21 @@ +#include +#include + +#include "print.h" + +#define PRINT_ERROR_PREFIX "ERROR: " +#define PRINT_ERROR_SUFFIX "\n" + +void +print_error(const char *const format, ...) +{ + fprintf(stderr, PRINT_ERROR_PREFIX); + + va_list args; + + va_start(args, format); + vfprintf(stderr, format, args); + va_end(args); + + fprintf(stderr, PRINT_ERROR_SUFFIX); +} diff --git a/src/print.h b/src/print.h new file mode 100644 index 0000000..7992087 --- /dev/null +++ b/src/print.h @@ -0,0 +1,6 @@ +#ifndef PRINT_H +#define PRINT_H + +void print_error(const char *const format, ...); + +#endif /* PRINT_H */ diff --git a/src/resources.c b/src/resources.c new file mode 100644 index 0000000..3eebd1c --- /dev/null +++ b/src/resources.c @@ -0,0 +1,44 @@ +#include +#include + +#include "resources.h" + +void +resources_init(resources_t *const res) +{ + res->in_file = NULL; + res->ref_file = NULL; + res->out_file = NULL; + res->in_buffer = NULL; + res->ref_buffer = NULL; + res->out_buffer = NULL; +} + +void +resources_free(resources_t *const res) +{ + if (res->in_file != NULL) { + fclose(res->in_file); + res->in_file = NULL; + } + if (res->ref_file != NULL) { + fclose(res->ref_file); + res->ref_file = NULL; + } + if (res->out_file != NULL) { + fclose(res->out_file); + res->out_file = NULL; + } + if (res->in_buffer != NULL) { + free(res->in_buffer); + res->in_buffer = NULL; + } + if (res->ref_buffer != NULL) { + free(res->ref_buffer); + res->ref_buffer = NULL; + } + if (res->out_buffer != NULL) { + free(res->out_buffer); + res->out_buffer = NULL; + } +} diff --git a/src/resources.h b/src/resources.h new file mode 100644 index 0000000..0cf9777 --- /dev/null +++ b/src/resources.h @@ -0,0 +1,17 @@ +#ifndef RESOURCES_H +#define RESOURCES_H + +typedef struct { + FILE *in_file; + FILE *ref_file; + FILE *out_file; + + char *in_buffer; + char *ref_buffer; + char *out_buffer; +} resources_t; + +void resources_init(resources_t *const res); +void resources_free(resources_t *const res); + +#endif /* RESOURCES_H */ diff --git a/tests/Makefile b/tests/Makefile index e202c55..fc86402 100644 --- a/tests/Makefile +++ b/tests/Makefile @@ -1,4 +1,4 @@ -PROGRAM_EXEC=../$(PROGRAM_NAME) +PROGRAM_EXEC=../src/$(PROGRAM_NAME) all: sh ./001-no_options_given.sh $(PROGRAM_EXEC) -- cgit v1.2.3