* 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
*
* Based in part on BusyBox tar, Debian dpkg-deb and GNU ar.
*
* 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 20 September 2000
*/
-#include <stdio.h>
-#include <string.h>
#include <fcntl.h>
-#include <errno.h>
-#include <ctype.h>
-#include <time.h>
-#include <utime.h>
-#include <unistd.h>
+#include <string.h>
#include <stdlib.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <malloc.h>
+#include <getopt.h>
+#include <unistd.h>
#include "busybox.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 RECURSIVE 32
-
-#define MAX_NAME_LENGTH 100
-
-//#define BB_DECLARE_EXTERN
-//#define bb_need_io_error
-//#include "messages.c"
-
-//#define BB_AR_EXPERIMENTAL_UNTAR
-
-#if defined BB_AR_EXPERIMENTAL_UNTAR
-typedef struct rawTarHeader {
- char name[100]; /* 0-99 */
- char mode[8]; /* 100-107 */
- char uid[8]; /* 108-115 */
- char gid[8]; /* 116-123 */
- char size[12]; /* 124-135 */
- char mtime[12]; /* 136-147 */
- char chksum[8]; /* 148-155 */
- char typeflag; /* 156-156 */
- char linkname[100]; /* 157-256 */
- char magic[6]; /* 257-262 */
- char version[2]; /* 263-264 */
- char uname[32]; /* 265-296 */
- char gname[32]; /* 297-328 */
- char devmajor[8]; /* 329-336 */
- char devminor[8]; /* 337-344 */
- char prefix[155]; /* 345-499 */
- char padding[12]; /* 500-512 */
-} rawTarHeader_t;
-#endif
-
-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 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;
-typedef struct headerL {
- char name[MAX_NAME_LENGTH];
- size_t size;
- uid_t uid;
- gid_t gid;
- mode_t mode;
- time_t mtime;
- off_t offset;
- struct headerL *next;
-} headerL_t;
-
-#if defined BB_AR_EXPERIMENTAL_UNTAR
/*
- * identify Tar header (magic field) and reset srcFd to entry position
+ * return the headerL_t struct for the filename descriptor
*/
-static int checkTarMagic(int srcFd)
-{
- off_t headerStart;
- char magic[6];
-
- headerStart = lseek(srcFd, 0, SEEK_CUR);
- lseek(srcFd, (off_t) 257, SEEK_CUR);
- fullRead(srcFd, magic, 6);
- lseek(srcFd, headerStart, SEEK_SET);
- if (strncmp(magic, "ustar", 5)!=0)
- return(FALSE);
- return(TRUE);
-}
-
-
-static int readTarHeader(int srcFd, headerL_t *current)
+extern ar_headers_t get_headers(int srcFd)
{
- rawTarHeader_t rawTarHeader;
- unsigned char *temp = (unsigned char *) &rawTarHeader;
- long sum = 0;
- int i;
- off_t initialOffset;
-
- initialOffset = lseek(srcFd, 0, SEEK_CUR);
- if (fullRead(srcFd, (char *) &rawTarHeader, 512) != 512) {
- lseek(srcFd, initialOffset, SEEK_SET);
- return(FALSE);
- }
- for (i = 0; i < 148 ; i++)
- sum += temp[i];
- sum += ' ' * 8;
- for (i = 156; i < 512 ; i++)
- sum += temp[i];
- if (sum!= strtol(rawTarHeader.chksum, NULL, 8))
- return(FALSE);
- sscanf(rawTarHeader.name, "%s", current->name);
- current->size = strtol(rawTarHeader.size, NULL, 8);
- current->uid = strtol(rawTarHeader.uid, NULL, 8);
- current->gid = strtol(rawTarHeader.gid, NULL, 8);
- current->mode = strtol(rawTarHeader.mode, NULL, 8);
- current->mtime = strtol(rawTarHeader.mtime, NULL, 8);
- current->offset = lseek(srcFd, 0 , SEEK_CUR);
-
- current->next = (headerL_t *) xmalloc(sizeof(headerL_t));
- current = current->next;
- return(TRUE);
-}
-#endif
-
-/*
- * identify Ar header (magic) and reset srcFd to entry position
- */
-static int checkArMagic(int srcFd)
-{
- off_t headerStart;
- char arMagic[8];
-
- headerStart = lseek(srcFd, 0, SEEK_CUR);
- if (fullRead(srcFd, arMagic, 8) != 8) {
- errorMsg("fatal error\n");
- return (FALSE);
- }
- lseek(srcFd, headerStart, SEEK_SET);
-
- if (strncmp(arMagic,"!<arch>",7) != 0)
- return(FALSE);
- return(TRUE);
-}
-
-/*
- * get, check and correct the converted header
- */
-static int readArEntry(int srcFd, headerL_t *entry)
-{
- size_t nameLength;
- rawArHeader_t rawArHeader;
- off_t initialOffset;
-
- initialOffset = lseek(srcFd, 0, SEEK_CUR);
- if (fullRead(srcFd, (char *) &rawArHeader, 60) != 60) {
- lseek(srcFd, initialOffset, SEEK_SET);
- return(FALSE);
- }
- if ((rawArHeader.fmag[0]!='`') || (rawArHeader.fmag[1]!='\n')) {
- lseek(srcFd, initialOffset, SEEK_SET);
- return(FALSE);
- }
-
- strncpy(entry->name, rawArHeader.name, 16);
- nameLength=strcspn(entry->name, " \\");
- entry->name[nameLength]='\0';
- parse_mode(rawArHeader.mode, &entry->mode);
- entry->mtime = atoi(rawArHeader.date);
- entry->uid = atoi(rawArHeader.uid);
- entry->gid = atoi(rawArHeader.gid);
- entry->size = (size_t) atoi(rawArHeader.size);
- entry->offset = initialOffset + (off_t) 60;
-
- nameLength = strcspn(entry->name, "/");
+ 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;
+
+ ar_headers_t *head, *entry;
+ char ar_magic[8];
+ char *long_name=NULL;
- /* handle GNU style short filenames, strip trailing '/' */
- if (nameLength > 0)
- entry->name[nameLength]='\0';
+ head = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
+ entry = (ar_headers_t *) xmalloc(sizeof(ar_headers_t));
- /* handle GNU style long filenames */
- if (nameLength == 0) {
- /* escape from recursive call */
- if (entry->name[1]=='0')
- return(TRUE);
-
- /* the data section contains the real filename */
- if (entry->name[1]=='/') {
- char tempName[MAX_NAME_LENGTH];
-
- if (entry->size > MAX_NAME_LENGTH)
- entry->size = MAX_NAME_LENGTH;
- fullRead(srcFd, tempName, entry->size);
- tempName[entry->size-3]='\0';
-
- /* read the second header for this entry */
- /* be carefull, this is recursive */
- if (readArEntry(srcFd, entry)==FALSE)
- return(FALSE);
+ /* 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");
+
+ 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 */
+ }
- if ((entry->name[0]='/') && (entry->name[1]='0'))
- strcpy(entry->name, tempName);
+ 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 {
- errorMsg("Invalid long filename\n");
- return(FALSE);
+ /* 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]);
}
}
- }
- return(TRUE);
-}
-
-/*
- * return the headerL_t struct for the specified filename
- */
-static headerL_t *getHeaders(int srcFd, headerL_t *head, int funct)
-{
-#if defined BB_AR_EXPERIMENTAL_UNTAR
- int tar=FALSE;
-#endif
- int ar=FALSE;
- headerL_t *list;
- off_t initialOffset;
-
- list = (headerL_t *) xmalloc(sizeof(headerL_t));
- initialOffset=lseek(srcFd, 0, SEEK_CUR);
- if (checkArMagic(srcFd)==TRUE)
- ar=TRUE;
-
-#if defined BB_AR_EXPERIMENTAL_UNTAR
- if (checkTarMagic(srcFd)==TRUE)
- tar=TRUE;
-
- if (tar==TRUE) {
- while(readTarHeader(srcFd, list)==TRUE) {
- off_t tarOffset;
- list->next = (headerL_t *) xmalloc(sizeof(headerL_t));
- *list->next = *head;
- *head = *list;
-
- /* recursive check for sub-archives */
- if ((funct & RECURSIVE) == RECURSIVE)
- head = getHeaders(srcFd, head, funct);
- tarOffset = (off_t) head->size/512;
- if ( head->size % 512 > 0)
- tarOffset++;
- tarOffset=tarOffset*512;
- lseek(srcFd, head->offset + tarOffset, SEEK_SET);
- }
- }
-#endif
-
- if (ar==TRUE) {
- lseek(srcFd, 8, SEEK_CUR);
- while(1) {
- if (readArEntry(srcFd, list) == FALSE) {
- lseek(srcFd, ++initialOffset, SEEK_CUR);
- if (readArEntry(srcFd, list) == FALSE)
- return(head);
- }
- list->next = (headerL_t *) xmalloc(sizeof(headerL_t));
- *list->next = *head;
- *head = *list;
- /* recursive check for sub-archives */
- if (funct & RECURSIVE)
- head = getHeaders(srcFd, head, funct);
- lseek(srcFd, head->offset + head->size, SEEK_SET);
+ else {
+ /* short filenames */
+ entry->name = xmalloc(16);
+ strncpy(entry->name, raw_ar_header.name, 16);
}
+ entry->name[strcspn(entry->name, " /")]='\0';
+
+ /* 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);
+
+ /* 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);
}
- return(head);
-}
-
-/*
- * find an entry in the linked list matching the filename
- */
-static headerL_t *findEntry(headerL_t *head, const char *filename)
-{
- while(head->next != NULL) {
- if (strcmp(filename, head->name)==0)
- return(head);
- head=head->next;
- }
- return(NULL);
+ 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;
- headerL_t *header, *entry, *extractList;
- while ((opt = getopt(argc, argv, "ovtpxR")) != -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 |= PRESERVE_DATE;
+ funct |= preserve_date;
break;
case 'v':
- funct |= VERBOSE;
+ funct |= verbose;
break;
case 't':
- funct |= DISPLAY;
- break;
- case 'x':
- funct |= EXT_TO_FILE;
+ funct |= display;
break;
case 'p':
- funct |= EXT_TO_STDOUT;
+ funct |= extract_to_stdout;
break;
- case 'R':
- funct |= RECURSIVE;
+ case 'x':
+ funct |= extract_to_file;
break;
default:
usage(ar_usage);
usage(ar_usage);
if ( (srcFd = open(argv[optind], O_RDONLY)) < 0)
- fatalError("Cannot read %s\n", argv[optind]);
+ error_msg_and_die("Cannot read %s\n", argv[optind]);
- optind++;
- entry = (headerL_t *) xmalloc(sizeof(headerL_t));
- header = (headerL_t *) xmalloc(sizeof(headerL_t));
- extractList = (headerL_t *) xmalloc(sizeof(headerL_t));
+ optind++;
+ head = get_headers(srcFd);
- header = getHeaders(srcFd, header, funct);
/* find files to extract or display */
- if (optind<argc) {
- /* only handle specified files */
- while(optind < argc) {
- if ( (entry = findEntry(header, argv[optind])) != NULL) {
- entry->next = (headerL_t *) xmalloc(sizeof(headerL_t));
- *entry->next = *extractList;
- *extractList = *entry;
+ /* 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;
}
- optind++;
- }
+ ar_entry=ar_entry->next;
+ }
+ }
+
+ /* if individual files not found extract all files */
+ if (extract_list->next==NULL) {
+ extract_list = &head;
}
- else
- extractList = header;
- while(extractList->next != NULL) {
- if (funct & EXT_TO_FILE) {
- if (isDirectory(extractList->name, TRUE, NULL)==FALSE)
- createPath(extractList->name, 0666);
- dstFd = open(extractList->name, O_WRONLY | O_CREAT, extractList->mode);
- lseek(srcFd, extractList->offset, SEEK_SET);
- copySubFile(srcFd, dstFd, (size_t) extractList->size);
+ /* 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);
}
- if (funct & EXT_TO_STDOUT) {
- lseek(srcFd, extractList->offset, SEEK_SET);
- copySubFile(srcFd, fileno(stdout), (size_t) extractList->size);
+ 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)) {
- if (funct & VERBOSE)
- printf("%s %d/%d %8d %s ", modeString(extractList->mode),
- extractList->uid, extractList->gid,
- extractList->size, timeString(extractList->mtime));
- printf("%s\n", extractList->name);
+ if ((funct & display) || (funct & verbose)){
+ printf("%s\n", extract_list->name);
}
- extractList=extractList->next;
+ extract_list=extract_list->next;
}
return EXIT_SUCCESS;
}