From 4f381aa35d66185b97bfba62d4002857660118f1 Mon Sep 17 00:00:00 2001 From: Gaspartcho <93390411+Gaspartcho@users.noreply.github.com> Date: Fri, 23 Feb 2024 18:59:56 +0100 Subject: Update extract: .tgz and +100 char name support (#73) * added tar support * fixed small mistake * added support for utar + removed microtar as submodule * will finish this tomorow * added support for gnu and other * re-done all small changes * fixed pax format (hopefully) * added a r to 'curent_read' --- lib/microtar/src/microtar.c | 434 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 434 insertions(+) create mode 100644 lib/microtar/src/microtar.c (limited to 'lib/microtar/src/microtar.c') diff --git a/lib/microtar/src/microtar.c b/lib/microtar/src/microtar.c new file mode 100644 index 0000000..1cd9920 --- /dev/null +++ b/lib/microtar/src/microtar.c @@ -0,0 +1,434 @@ +/* + * Copyright (c) 2017 rxi + * Copyright (c) 2024 Gaspartcho + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to + * deal in the Software without restriction, including without limitation the + * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include +#include +#include + +#include "microtar.h" + +typedef struct { + // Original tar header fields + char file_path[100]; + char file_mode[8]; + char owner_user_id[8]; + char owner_group_id[8]; + char file_size[12]; + char file_mtime[12]; + char header_checksum[8]; + char file_type; + char link_path[100]; + + // New UStar fields + char magic_bytes[6]; + char version[2]; + char owner_user_name[32]; + char owner_group_name[32]; + char device_major_number[8]; + char device_minor_number[8]; + char prefix[155]; + + char padding[12]; +} mtar_raw_header_t; + + +static unsigned round_up(unsigned n, unsigned incr) { + return n + (incr - n % incr) % incr; +} + + +static unsigned checksum(const mtar_raw_header_t* rh) { + unsigned i; + unsigned char *p = (unsigned char*) rh; + unsigned res = 256; + for (i = 0; i < offsetof(mtar_raw_header_t, header_checksum); i++) { + res += p[i]; + } + for (i = offsetof(mtar_raw_header_t, file_type); i < sizeof(*rh); i++) { + res += p[i]; + } + return res; +} + + +static int tread(mtar_t *tar, void *data, unsigned size) { + int err = tar->read(tar, data, size); + tar->pos += size; + return err; +} + + +static int twrite(mtar_t *tar, const void *data, unsigned size) { + int err = tar->write(tar, data, size); + tar->pos += size; + return err; +} + + +static int write_null_bytes(mtar_t *tar, int n) { + int i, err; + char nul = '\0'; + for (i = 0; i < n; i++) { + err = twrite(tar, &nul, 1); + if (err) { + return err; + } + } + return MTAR_ESUCCESS; +} + +static int read_filename(char *dest, const char *name, const char *prefix) { + // If there's no prefix, use name directly + if (prefix[0] == '\0') { + strcpy(dest, name); + dest[100] = '\0'; + return MTAR_ESUCCESS; + } + + // If there is a prefix, the path is: '/' + strcpy(dest, prefix); + strcat(dest, "/"); + strcat(dest, name); + dest[256] = '\0'; + + return MTAR_ESUCCESS; +} + + +static int raw_to_header(mtar_header_t *h, const mtar_raw_header_t *rh) { + unsigned chksum1, chksum2; + + /* If the checksum starts with a null byte we assume the record is NULL */ + if (*rh->header_checksum == '\0') { + return MTAR_ENULLRECORD; + } + + /* Build and compare checksum */ + chksum1 = checksum(rh); + sscanf(rh->header_checksum, "%o", &chksum2); + if (chksum1 != chksum2) { + return MTAR_EBADCHKSUM; + } + + /* Load raw header into header */ + sscanf(rh->file_mode, "%o", &h->mode); + sscanf(rh->owner_user_id, "%o", &h->owner); + sscanf(rh->file_size, "%o", &h->size); + sscanf(rh->file_mtime, "%o", &h->mtime); + h->type = rh->file_type; + read_filename(h->name, rh->file_path, rh->prefix); + read_filename(h->linkname, rh->link_path, rh->prefix); + + return MTAR_ESUCCESS; +} + + +static int header_to_raw(mtar_raw_header_t *rh, const mtar_header_t *h) { + unsigned chksum; + + /* Load header into raw header */ + memset(rh, 0, sizeof(*rh)); + sprintf(rh->file_mode , "%o", h->mode); + sprintf(rh->owner_user_id, "%o", h->owner); + sprintf(rh->file_size, "%o", h->size); + sprintf(rh->file_mtime, "%o", h->mtime); + rh->file_type = h->type ? h->type : MTAR_TREG; + strcpy(rh->file_path, h->name); + strcpy(rh->link_path, h->linkname); + + + /* Calculate and write checksum */ + chksum = checksum(rh); + sprintf(rh->header_checksum, "%06o", chksum); + rh->header_checksum[7] = ' '; + + return MTAR_ESUCCESS; +} + + +const char* mtar_strerror(int err) { + switch (err) { + case MTAR_ESUCCESS : return "success"; + case MTAR_EFAILURE : return "failure"; + case MTAR_EOPENFAIL : return "could not open"; + case MTAR_EREADFAIL : return "could not read"; + case MTAR_EWRITEFAIL : return "could not write"; + case MTAR_ESEEKFAIL : return "could not seek"; + case MTAR_EBADCHKSUM : return "bad checksum"; + case MTAR_ENULLRECORD : return "null record"; + case MTAR_ENOTFOUND : return "file not found"; + } + return "unknown error"; +} + + +static int file_write(mtar_t *tar, const void *data, unsigned size) { + unsigned res = fwrite(data, 1, size, tar->stream); + return (res == size) ? MTAR_ESUCCESS : MTAR_EWRITEFAIL; +} + +static int file_read(mtar_t *tar, void *data, unsigned size) { + unsigned res = fread(data, 1, size, tar->stream); + return (res == size) ? MTAR_ESUCCESS : MTAR_EREADFAIL; +} + +static int file_seek(mtar_t *tar, unsigned offset) { + int res = fseek(tar->stream, offset, SEEK_SET); + return (res == 0) ? MTAR_ESUCCESS : MTAR_ESEEKFAIL; +} + +static int file_close(mtar_t *tar) { + fclose(tar->stream); + return MTAR_ESUCCESS; +} + + +int mtar_open(mtar_t *tar, const char *filename, const char *mode) { + int err; + mtar_header_t h; + + /* Init tar struct and functions */ + memset(tar, 0, sizeof(*tar)); + tar->write = file_write; + tar->read = file_read; + tar->seek = file_seek; + tar->close = file_close; + + /* Assure mode is always binary */ + if ( strchr(mode, 'r') ) mode = "rb"; + if ( strchr(mode, 'w') ) mode = "wb"; + if ( strchr(mode, 'a') ) mode = "ab"; + /* Open file */ + tar->stream = fopen(filename, mode); + if (!tar->stream) { + return MTAR_EOPENFAIL; + } + /* Read first header to check it is valid if mode is `r` */ + if (*mode == 'r') { + err = mtar_read_header(tar, &h); + if (err != MTAR_ESUCCESS) { + mtar_close(tar); + return err; + } + } + + /* Return ok */ + return MTAR_ESUCCESS; +} + + +int mtar_close(mtar_t *tar) { + return tar->close(tar); +} + + +int mtar_seek(mtar_t *tar, unsigned pos) { + int err = tar->seek(tar, pos); + tar->pos = pos; + return err; +} + + +int mtar_rewind(mtar_t *tar) { + tar->remaining_data = 0; + tar->last_header = 0; + return mtar_seek(tar, 0); +} + + +int mtar_next(mtar_t *tar) { + int err, n; + mtar_header_t h; + /* Load header */ + err = mtar_read_header(tar, &h); + if (err) { + return err; + } + /* Seek to next record */ + n = round_up(h.size, 512) + sizeof(mtar_raw_header_t); + return mtar_seek(tar, tar->pos + n); +} + + +int mtar_find(mtar_t *tar, const char *name, mtar_header_t *h) { + int err; + mtar_header_t header; + /* Start at beginning */ + err = mtar_rewind(tar); + if (err) { + return err; + } + /* Iterate all files until we hit an error or find the file */ + while ( (err = mtar_read_header(tar, &header)) == MTAR_ESUCCESS ) { + if ( !strcmp(header.name, name) ) { + if (h) { + *h = header; + } + return MTAR_ESUCCESS; + } + mtar_next(tar); + } + /* Return error */ + if (err == MTAR_ENULLRECORD) { + err = MTAR_ENOTFOUND; + } + return err; +} + + +int mtar_read_header(mtar_t *tar, mtar_header_t *h) { + int err; + mtar_raw_header_t rh; + /* Save header position */ + tar->last_header = tar->pos; + /* Read raw header */ + err = tread(tar, &rh, sizeof(rh)); + if (err) { + return err; + } + /* Seek back to start of header */ + err = mtar_seek(tar, tar->last_header); + if (err) { + return err; + } + /* Load raw header into header struct and return */ + return raw_to_header(h, &rh); +} + + +int mtar_update_header(mtar_header_t *h, mtar_header_t *oh) { + if (oh->mode) h->mode = oh->mode; + if (oh->owner) h->owner = oh->owner; + if (oh->size) h->size = oh->size; + if (oh->mtime) h->mtime = oh->mtime; + if (oh->type) h->type = oh->type; + + if (oh->name[0] != '\0') strcpy(h->name, oh->name); + if (oh->linkname[0] != '\0') strcpy(h->linkname, oh->linkname); + + return MTAR_ESUCCESS; +} + + +int mtar_clear_header(mtar_header_t *h){ + h->mode = 0; + h->owner = 0; + h->size = 0; + h->mtime = 0; + h->type = 0; + bzero(h->name, strlen(h->name)); + bzero(h->linkname, strlen(h->linkname)); + + return MTAR_ESUCCESS; +} + + +int mtar_read_data(mtar_t *tar, void *ptr, unsigned size) { + int err; + /* If we have no remaining data then this is the first read, we get the size, + * set the remaining data and seek to the beginning of the data */ + if (tar->remaining_data == 0) { + mtar_header_t h; + /* Read header */ + err = mtar_read_header(tar, &h); + if (err) { + return err; + } + /* Seek past header and init remaining data */ + err = mtar_seek(tar, tar->pos + sizeof(mtar_raw_header_t)); + if (err) { + return err; + } + tar->remaining_data = h.size; + } + /* Read data */ + err = tread(tar, ptr, size); + if (err) { + return err; + } + tar->remaining_data -= size; + /* If there is no remaining data we've finished reading and seek back to the + * header */ + if (tar->remaining_data == 0) { + return mtar_seek(tar, tar->last_header); + } + return MTAR_ESUCCESS; +} + + +int mtar_write_header(mtar_t *tar, const mtar_header_t *h) { + mtar_raw_header_t rh; + /* Build raw header and write */ + header_to_raw(&rh, h); + tar->remaining_data = h->size; + return twrite(tar, &rh, sizeof(rh)); +} + + +int mtar_write_file_header(mtar_t *tar, const char *name, unsigned size) { + mtar_header_t h; + /* Build header */ + memset(&h, 0, sizeof(h)); + strcpy(h.name, name); + h.size = size; + h.type = MTAR_TREG; + h.mode = 0664; + /* Write header */ + return mtar_write_header(tar, &h); +} + + +int mtar_write_dir_header(mtar_t *tar, const char *name) { + mtar_header_t h; + /* Build header */ + memset(&h, 0, sizeof(h)); + strcpy(h.name, name); + h.type = MTAR_TDIR; + h.mode = 0775; + /* Write header */ + return mtar_write_header(tar, &h); +} + + +int mtar_write_data(mtar_t *tar, const void *data, unsigned size) { + int err; + /* Write data */ + err = twrite(tar, data, size); + if (err) { + return err; + } + tar->remaining_data -= size; + /* Write padding if we've written all the data for this file */ + if (tar->remaining_data == 0) { + return write_null_bytes(tar, round_up(tar->pos, 512) - tar->pos); + } + return MTAR_ESUCCESS; +} + + +int mtar_finalize(mtar_t *tar) { + /* Write two NULL records */ + return write_null_bytes(tar, sizeof(mtar_raw_header_t) * 2); +} + -- cgit v1.2.3