* Mini ar implementation for busybox
*
* Copyright (C) 2000 by Glenn McGrath
- * Written by Glenn McGrath <bug1@netconnect.com.au> 1 June 2000
+ * Written by Glenn McGrath <bug1@optushome.com.au> 1 June 2000
*
- * Modified 8 August 2000 by Glenn McGrath
- * - now uses getopt
- * - moved copySubFile function to utilities.c
- * - creates linked list of all headers
- * - easily accessable to other busybox functions
- *
* Based in part on BusyBox tar, Debian dpkg-deb and GNU ar.
*
* This program is free software; you can redistribute it and/or modify
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
- * Last modified 25 August 2000
*/
-#include <stdio.h>
#include <fcntl.h>
-#include <errno.h>
-#include <ctype.h>
-#include <time.h>
-#include <utime.h>
-#include <sys/types.h>
-#include "internal.h"
-
-#define BLOCK_SIZE 60
-#define PRESERVE_DATE 1 /* preserve original dates */
-#define VERBOSE 2 /* be verbose */
-#define DISPLAY 4 /* display contents */
-#define EXT_TO_FILE 8 /* extract contents of archive */
-#define EXT_TO_STDOUT 16 /* extract to stdout */
-
-#define BB_DECLARE_EXTERN
-#define bb_need_io_error
-#include "messages.c"
+#include <string.h>
+#include <stdlib.h>
+#include <getopt.h>
+#include <unistd.h>
+#include "busybox.h"
-typedef struct rawArHeader { /* Byte Offset */
- char name[16]; /* 0-15 */
- char date[12]; /* 16-27 */
- char uid[6], gid[6]; /* 28-39 */
- char mode[8]; /* 40-47 */
- char size[10]; /* 48-57 */
- char fmag[2]; /* 58-59 */
-} rawArHeader_t;
-
-typedef struct headerL {
- char name[16];
- size_t size;
- uid_t uid;
- gid_t gid;
- mode_t mode;
- time_t mtime;
- off_t offset;
- struct headerL *next;
-} headerL_t;
+typedef struct ar_headers_s {
+ char *name;
+ size_t size;
+ uid_t uid;
+ gid_t gid;
+ mode_t mode;
+ time_t mtime;
+ off_t offset;
+ struct ar_headers_s *next;
+} ar_headers_t;
/*
- * populate linked list with all ar file entries and offset
+ * return the headerL_t struct for the filename descriptor
*/
-static int parseArArchive(int srcFd, headerL_t *current)
+extern ar_headers_t get_headers(int srcFd)
{
- off_t lastOffset=0, thisOffset=0;
- char arVersion[8];
- rawArHeader_t rawArHeader;
-
- lseek(srcFd, 0, SEEK_SET);
- if (fullRead(srcFd, arVersion, 8) <= 0) {
- errorMsg("Invalid header magic\n");
- return (FALSE);
- }
- if (strncmp(arVersion,"!<arch>",7) != 0) {
- errorMsg("This doesnt appear to be an ar archive\n");
- return(FALSE);
- }
- while (fullRead(srcFd, (char *) &rawArHeader, 60) == 60) {
- if ( (rawArHeader.fmag[0] == '`') &&
- (rawArHeader.fmag[1] == '\n')) {
- sscanf(rawArHeader.name, "%s", current->name);
- parse_mode(rawArHeader.mode, ¤t->mode);
- current->mtime = atoi(rawArHeader.date);
- current->uid = atoi(rawArHeader.uid);
- current->gid = atoi(rawArHeader.gid);
- current->size = (size_t) atoi(rawArHeader.size);
- current->offset = lseek(srcFd, 0 , SEEK_CUR);
- current->next = (headerL_t *) xmalloc(sizeof(headerL_t));
- lastOffset = lseek(srcFd, (off_t) current->size, SEEK_CUR);
- current = current->next;
- }
- else { /* GNU ar has an extra char after data */
- thisOffset=lseek(srcFd, 0, SEEK_CUR);
- if ( (thisOffset - lastOffset) > ((off_t) 61) )
- return(FALSE);
- lseek(srcFd, thisOffset - 59, SEEK_SET);
- }
- }
- return(FALSE);
-}
+ typedef struct raw_ar_header_s { /* Byte Offset */
+ char name[16]; /* 0-15 */
+ char date[12]; /* 16-27 */
+ char uid[6];
+ char gid[6]; /* 28-39 */
+ char mode[8]; /* 40-47 */
+ char size[10]; /* 48-57 */
+ char fmag[2]; /* 58-59 */
+ } raw_ar_header_t;
+ raw_ar_header_t raw_ar_header;
-/*
- * return the headerL_t struct for the specified filename
- */
-static headerL_t *getSubFileHeader(int srcFd, const char filename[16])
-{
- headerL_t *list;
- list = xmalloc(sizeof(headerL_t));
+ ar_headers_t *head, *entry;
+ char ar_magic[8];
+ char *long_name=NULL;
+
+ head = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+ entry = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+
+ /* check ar magic */
+ if (full_read(srcFd, ar_magic, 8) != 8)
+ error_msg_and_die("cannot read magic\n");
+ if (strncmp(ar_magic,"!<arch>",7) != 0)
+ error_msg_and_die("invalid magic\n");
- parseArArchive(srcFd, list);
- while (list->next != NULL) {
- if (strncmp(list->name, filename, strlen(filename))==0)
- return(list);
- list=list->next;
- }
- return(NULL);
-}
+ while (full_read(srcFd, (char *) &raw_ar_header, 60)==60) {
+ /* check the end of header markers are valid */
+ if ((raw_ar_header.fmag[0]!='`') || (raw_ar_header.fmag[1]!='\n')) {
+ char newline[1];
+ if (raw_ar_header.fmag[1]!='`') {
+ break;
+ }
+ /* some version of ar, have an extra '\n' after each entry */
+ read(srcFd, newline, 1);
+ if (newline[0]!='\n') {
+ break;
+ }
+ /* fix up the header, we started reading 1 byte too early due to a '\n' */
+ memmove((char *) &raw_ar_header, (char *)&raw_ar_header+1, 59);
+ /* dont worry about adding the last '\n', we dont need it now */
+ }
+
+ entry->size = (size_t) atoi(raw_ar_header.size);
+ /* long filenames have '/' as the first character */
+ if (raw_ar_header.name[0] == '/') {
+ if (raw_ar_header.name[1] == '/') {
+ /* multiple long filenames are stored as data in one entry */
+ long_name = (char *) xrealloc(long_name, entry->size);
+ full_read(srcFd, long_name, entry->size);
+ continue;
+ }
+ else {
+ /* The number after the '/' indicates the offset in the ar data section
+ (saved in variable long_name) that conatains the real filename */
+ const int long_name_offset = (int) atoi((char *) &raw_ar_header.name[1]);
+ entry->name = xmalloc(strlen(&long_name[long_name_offset]));
+ strcpy(entry->name, &long_name[long_name_offset]);
+ }
+ }
+ else {
+ /* short filenames */
+ entry->name = xmalloc(16);
+ strncpy(entry->name, raw_ar_header.name, 16);
+ }
+ entry->name[strcspn(entry->name, " /")]='\0';
-/*
- * populate linked list with all ar file entries and offset
- */
-static int displayEntry(int srcFd, const char filename[16], int funct)
-{
- headerL_t *file;
+ /* convert the rest of the now valid char header to its typed struct */
+ parse_mode(raw_ar_header.mode, &entry->mode);
+ entry->mtime = atoi(raw_ar_header.date);
+ entry->uid = atoi(raw_ar_header.uid);
+ entry->gid = atoi(raw_ar_header.gid);
+ entry->offset = lseek(srcFd, 0, SEEK_CUR);
- if ((file = getSubFileHeader(srcFd, filename)) == NULL)
- return(FALSE);
- if ((funct & VERBOSE) == VERBOSE) {
- printf("%s %d/%d %8d %s ", modeString(file->mode), file->uid, file->gid, file->size, timeString(file->mtime));
+ /* add this entries header to our combined list */
+ entry->next = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+ *entry->next = *head;
+ *head = *entry;
+ lseek(srcFd, (off_t) entry->size, SEEK_CUR);
}
- printf("%s\n", file->name);
- return(TRUE);
-}
-
-static int extractAr(int srcFd, int dstFd, const char filename[16])
-{
- headerL_t *file;
-
- if ( (file = getSubFileHeader(srcFd, filename)) == NULL)
- return(FALSE);
- lseek(srcFd, file->offset, SEEK_SET);
- if (copySubFile(srcFd, dstFd, (size_t) file->size) == TRUE)
- return(TRUE);
- return(FALSE);
+ return(*head);
}
extern int ar_main(int argc, char **argv)
{
- int funct = 0, opt=0;
+ const int preserve_date = 1; /* preserve original dates */
+ const int verbose = 2; /* be verbose */
+ const int display = 4; /* display contents */
+ const int extract_to_file = 8; /* extract contents of archive */
+ const int extract_to_stdout = 16; /* extract to stdout */
+
+ int funct = 0, opt=0;
int srcFd=0, dstFd=0;
-
- while ((opt = getopt(argc, argv, "ovt:p:x:")) != -1) {
+
+ ar_headers_t head, *extract_list=NULL;
+
+ extract_list = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+
+ while ((opt = getopt(argc, argv, "ovtpx")) != -1) {
switch (opt) {
case 'o':
- funct = funct | PRESERVE_DATE;
+ funct |= preserve_date;
break;
case 'v':
- funct = funct | VERBOSE;
+ funct |= verbose;
break;
case 't':
- funct = funct | DISPLAY;
- case 'x':
- if (opt=='x') {
- funct = funct | EXT_TO_FILE;
- }
+ funct |= display;
+ break;
case 'p':
- if (opt=='p') {
- funct = funct | EXT_TO_STDOUT;
- }
- /* following is common to 't','x' and 'p' */
- if (optarg == NULL) {
- printf("expected a filename\n");
- return(FALSE);
- }
- if ( (srcFd = open(optarg, O_RDONLY)) < 0) {
- errorMsg("Cannot read %s\n", optarg);
- return (FALSE);
- }
+ funct |= extract_to_stdout;
+ break;
+ case 'x':
+ funct |= extract_to_file;
break;
default:
usage(ar_usage);
}
}
- /* check options not just preserve_dates and/or verbose */
- if (funct < 4) {
- usage(ar_usage);
- return(FALSE);
- }
+ /* check the src filename was specified */
+ if (optind == argc)
+ usage(ar_usage);
- /* find files to extract */
- if (optind<argc)
- for(; optind < argc; optind++) {
- if ( (funct & EXT_TO_FILE) == EXT_TO_FILE) {
- dstFd = open(argv[optind], O_WRONLY | O_CREAT);
- extractAr(srcFd, dstFd, argv[optind]);
+ if ( (srcFd = open(argv[optind], O_RDONLY)) < 0)
+ error_msg_and_die("Cannot read %s\n", argv[optind]);
+
+ optind++;
+ head = get_headers(srcFd);
+
+ /* find files to extract or display */
+ /* search through argv and build extract list */
+ for (;optind<argc; optind++) {
+ ar_headers_t *ar_entry;
+ ar_entry = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+ ar_entry = &head;
+ while (ar_entry->next != NULL) {
+ if (strcmp(argv[optind], ar_entry->name) == 0) {
+ ar_headers_t *tmp;
+ tmp = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+ *tmp = *extract_list;
+ *extract_list = *ar_entry;
+ extract_list->next = tmp;
+ break;
}
- if ( (funct & EXT_TO_STDOUT) == EXT_TO_STDOUT)
- extractAr(srcFd, fileno(stdout), argv[optind]);
- if ( (funct & DISPLAY) == DISPLAY)
- displayEntry(srcFd, argv[optind], funct);
+ ar_entry=ar_entry->next;
+ }
+ }
+
+ /* if individual files not found extract all files */
+ if (extract_list->next==NULL) {
+ extract_list = &head;
+ }
+
+ /* find files to extract or display */
+ while (extract_list->next != NULL) {
+ if (funct & extract_to_file) {
+ dstFd = open(extract_list->name, O_WRONLY | O_CREAT, extract_list->mode);
+ }
+ else if (funct & extract_to_stdout) {
+ dstFd = fileno(stdout);
+ }
+ if ((funct & extract_to_file) || (funct & extract_to_stdout)) {
+ lseek(srcFd, extract_list->offset, SEEK_SET);
+ copy_file_chunk(srcFd, dstFd, (size_t) extract_list->size);
}
- return (TRUE);
+ if (funct & verbose) {
+ printf("%s %d/%d %8d %s ", mode_string(extract_list->mode),
+ extract_list->uid, extract_list->gid,
+ extract_list->size, time_string(extract_list->mtime));
+ }
+ if ((funct & display) || (funct & verbose)){
+ printf("%s\n", extract_list->name);
+ }
+ extract_list=extract_list->next;
+ }
+ return EXIT_SUCCESS;
}