From d939939723fbc653f593d707d68448c9f162b300 Mon Sep 17 00:00:00 2001 From: Stephen Seo Date: Tue, 23 Jul 2024 15:28:59 +0900 Subject: [PATCH] Impl. archiving abs/rel-paths for symbolic links TODO: Choosing the ideal link based on if link points to an archived file. Extracting (creating) symbolic links from archive. --- src/archiver.c | 150 ++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 131 insertions(+), 19 deletions(-) diff --git a/src/archiver.c b/src/archiver.c index 9d47033..ea84868 100644 --- a/src/archiver.c +++ b/src/archiver.c @@ -28,6 +28,8 @@ SIMPLE_ARCHIVER_PLATFORM == SIMPLE_ARCHIVER_PLATFORM_LINUX #include #include +#include +#include #include #include #include @@ -668,31 +670,141 @@ int write_files_fn(void *data, void *ud) { #endif simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); - // Write absolute path length. - // TODO actually store absolute path. - // u16 = 0; - // No need to convert to big-endian since 0 is 0. - // simple_archiver_helper_16_bit_be(&u16); + // Get absolute path. + __attribute__((cleanup(free_malloced_memory))) void *abs_path = + realpath(file_info->filename, NULL); + if (!abs_path) { + fprintf(stderr, + "WARNING: Failed to get absolute path of link destination!\n"); + } - temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); - temp_to_write->buf = malloc(2); - temp_to_write->size = 2; - ((unsigned char *)temp_to_write->buf)[0] = 0; - ((unsigned char *)temp_to_write->buf)[1] = 0; - simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + // Get relative path. + __attribute__((cleanup(free_malloced_memory))) void *rel_path = NULL; + // First get absolute path of link. + // Get abs path to dirname of link. + unsigned int link_dir_path_len = strlen(file_info->filename) + 1; + __attribute__((cleanup(free_malloced_memory))) void *link_dir_path = + malloc(link_dir_path_len); + strncpy(link_dir_path, file_info->filename, link_dir_path_len); + char *link_dirname = dirname(link_dir_path); + __attribute__((cleanup(free_malloced_memory))) void *link_dir_abs_path = + realpath(link_dirname, NULL); + if (!link_dir_abs_path) { + fprintf(stderr, + "WARNING: Failed to get absolute path of link directory!\n"); + } else { + // Get basename of link to append. + __attribute__((cleanup(free_malloced_memory))) void *link_filename = + malloc(strlen(file_info->filename) + 1); + strncpy(link_filename, file_info->filename, + strlen(file_info->filename) + 1); + char *link_basename = basename(link_filename); + // Set up full path to link. + unsigned int link_path_len = strlen(link_dir_abs_path); + __attribute__((cleanup(free_malloced_memory))) void *combined_path = + malloc(link_path_len + 1 + strlen(link_basename) + 1); + strncpy(combined_path, link_dir_abs_path, link_path_len + 1); + ((char *)combined_path)[link_path_len] = '/'; + strncpy((char *)combined_path + link_path_len + 1, link_basename, + strlen(link_basename) + 1); + // fprintf(stderr, "DEBUG: abs_path: %s\nDEBUG: combined_path: %s\n", + // (char*)abs_path, (char*)combined_path); + // Compare paths to get relative path. + // Get first non-common char. + unsigned int idx; + unsigned int last_slash; + for (idx = 0, last_slash = 0; + idx < strlen(abs_path) && idx < strlen(combined_path); ++idx) { + if (((const char *)abs_path)[idx] != + ((const char *)combined_path)[idx]) { + break; + } else if (((const char *)abs_path)[idx] == '/') { + last_slash = idx + 1; + } + } + // Get substrings of both paths. + char *link_substr = (char *)combined_path + last_slash; + char *dest_substr = (char *)abs_path + last_slash; + rel_path = malloc(strlen(dest_substr) + 1); + strncpy(rel_path, dest_substr, strlen(dest_substr) + 1); + // fprintf(stderr, "DEBUG: link_substr: %s\nDEBUG: dest_substr: %s\n", + // link_substr, dest_substr); + // Generate the relative path. + int has_slash = 0; + idx = 0; + do { + for (; link_substr[idx] != '/' && link_substr[idx] != 0; ++idx); + if (link_substr[idx] == 0) { + has_slash = 0; + } else { + has_slash = 1; + char *new_rel_path = malloc(strlen(rel_path) + 1 + 3); + new_rel_path[0] = '.'; + new_rel_path[1] = '.'; + new_rel_path[2] = '/'; + strncpy(new_rel_path + 3, rel_path, strlen(rel_path) + 1); + free(rel_path); + rel_path = new_rel_path; + ++idx; + } + } while (has_slash); + } - // Write relative path length. - // TODO actually store relative path. + if (abs_path) { + // Write absolute path length. + u16 = strlen(abs_path); + simple_archiver_helper_16_bit_be(&u16); - temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); - temp_to_write->buf = malloc(2); - temp_to_write->size = 2; - ((unsigned char *)temp_to_write->buf)[0] = 0; - ((unsigned char *)temp_to_write->buf)[1] = 0; - simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(2); + temp_to_write->size = 2; + memcpy(temp_to_write->buf, &u16, 2); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + + // Write absolute path. + simple_archiver_helper_16_bit_be(&u16); + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(u16 + 1); + temp_to_write->size = u16 + 1; + strncpy(temp_to_write->buf, abs_path, u16 + 1); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + } else { + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(2); + temp_to_write->size = 2; + memset(temp_to_write->buf, 0, 2); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + } + + if (rel_path) { + // Write relative path length. + u16 = strlen(rel_path); + simple_archiver_helper_16_bit_be(&u16); + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(2); + temp_to_write->size = 2; + memcpy(temp_to_write->buf, &u16, 2); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + + // Write relative path. + simple_archiver_helper_16_bit_be(&u16); + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(u16 + 1); + temp_to_write->size = u16 + 1; + strncpy(temp_to_write->buf, rel_path, u16 + 1); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + } else { + temp_to_write = malloc(sizeof(SDArchiverInternalToWrite)); + temp_to_write->buf = malloc(2); + temp_to_write->size = 2; + memset(temp_to_write->buf, 0, 2); + simple_archiver_list_add(to_write, temp_to_write, free_internal_to_write); + } // Write all previously set data. fprintf(stderr, "Writing symlink info: %s\n", file_info->filename); + fprintf(stderr, " abs path: %s\n", (char *)abs_path); + fprintf(stderr, " rel path: %s\n", (char *)rel_path); simple_archiver_list_get(to_write, write_list_datas_fn, state->out_f); simple_archiver_list_free(&to_write); }