Now supports GNU style long filenames.

If no filenames are specifed to be (extracted/listed) it will act on
all files in the archive (i dont think the old version did this)

Code is structured to better support upcoming recursive extraction
functionality.

The old code was a bit strange in places, dont know what i was thinking.

1 files changed, 180 insertions, 85 deletions

diff --git a/ar.c b/ar.c
index 1c598fa..b758a69 100644
--- a/ar.c
+++ b/ar.c
@@ -5,12 +5,6 @@
  * Copyright (C) 2000 by Glenn McGrath
  * Written by Glenn McGrath <bug1@netconnect.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
@@ -27,15 +21,20 @@
  * 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
+ * Last modified 9 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 <stdlib.h>
 #include <sys/types.h>
+#include <sys/stat.h>
+#include <malloc.h>
 #include "internal.h"
 
 #define BLOCK_SIZE 60
@@ -45,11 +44,13 @@
 #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"
+#define MAX_NAME_LENGTH 100
+
+//#define BB_DECLARE_EXTERN
+//#define bb_need_io_error
+//#include "messages.c"
 
-typedef struct rawArHeader {            /* Byte Offset */
+typedef struct rawArHeader {    /* Byte Offset */
         char name[16];          /*  0-15 */
         char date[12];          /* 16-27 */
         char uid[6], gid[6];    /* 28-39 */
@@ -59,7 +60,7 @@ typedef struct rawArHeader {            /* Byte Offset */
 } rawArHeader_t;
 
 typedef struct headerL {
-	char name[16];
+	char name[MAX_NAME_LENGTH];
         size_t size;
         uid_t uid;
         gid_t gid;
@@ -70,86 +71,162 @@ typedef struct headerL {
 } headerL_t;
 
 /*
- * populate linked list with all ar file entries and offset 
+ * identify Ar header (magic) and set srcFd to first header entry 
  */
-static int parseArArchive(int srcFd, headerL_t *current)
+static int checkArMagic(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");
+        char arMagic[8];
+        if (fullRead(srcFd, arMagic, 8) != 8)
                 return (FALSE);
-        }
-        if (strncmp(arVersion,"!<arch>",7) != 0) {
-                errorMsg("This doesnt appear to be an ar archive\n");
+        
+	if (strncmp(arMagic,"!<arch>",7) != 0)
                 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, &current->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);
+	return(TRUE);
+}
+
+/*
+ * read, convert and check the raw ar header
+ * srcFd should be pointing to the start of header prior to entry
+ * srcFd will be pointing at the start of data after successful exit
+ * if returns FALSE srcFd is reset to initial position
+ */
+static int readRawArHeader(int srcFd, headerL_t *header)
+{
+	rawArHeader_t rawArHeader;
+	off_t	initialOffset;
+	size_t nameLength;
+	
+	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(header->name, rawArHeader.name, 16);
+	nameLength=strcspn(header->name, " \\");
+	header->name[nameLength]='\0';
+	parse_mode(rawArHeader.mode, &header->mode);
+        header->mtime = atoi(rawArHeader.date);
+        header->uid = atoi(rawArHeader.uid);
+        header->gid = atoi(rawArHeader.gid);
+        header->size = (size_t) atoi(rawArHeader.size);
+        header->offset = initialOffset + (off_t) 60;
+ 	return(TRUE); 
+}
+
+/*
+ * get, check and correct the converted header
+ */ 
+static int readArEntry(int srcFd, headerL_t *newEntry)
+{
+	size_t nameLength;
+
+	if(readRawArHeader(srcFd, newEntry)==FALSE)
+		return(FALSE);
+	
+	nameLength = strcspn(newEntry->name, "/");
+	
+	/* handle GNU style short filenames, strip trailing '/' */
+	if (nameLength > 0)
+		newEntry->name[nameLength]='\0';
+	
+	/* handle GNU style long filenames */ 
+	if (nameLength == 0) {
+		/* escape from recursive call */
+		if (newEntry->name[1]=='0') 
+			return(TRUE);
+
+		/* the data section contains the real filename */
+		if (newEntry->name[1]=='/') {
+			char tempName[MAX_NAME_LENGTH];
+
+			if (newEntry->size > MAX_NAME_LENGTH)
+				newEntry->size = MAX_NAME_LENGTH;
+			fullRead(srcFd, tempName, newEntry->size);
+			tempName[newEntry->size-3]='\0';
+			
+			/* read the second header for this entry */
+			/* be carefull, this is recursive */
+			if (readArEntry(srcFd, newEntry)==FALSE)
+				return(FALSE);
+		
+			if ((newEntry->name[0]='/') && (newEntry->name[1]='0'))
+				strcpy(newEntry->name, tempName);
+			else {
+				errorMsg("Invalid long filename\n");
+				return(FALSE);
+			}
+		}
+	}
+	return(TRUE);	
 }
 
 /*
  * return the headerL_t struct for the specified filename
  */
-static headerL_t *getSubFileHeader(int srcFd, const char filename[16])
+static headerL_t *getHeaders(int srcFd, headerL_t *head)
 {
-        headerL_t *list;
-	list = xmalloc(sizeof(headerL_t)); 
-
-        parseArArchive(srcFd, list);
-        while (list->next != NULL) {
-                if (strncmp(list->name, filename, strlen(filename))==0)
-                        return(list);
-                list=list->next;
-        }
-        return(NULL);
+	int arEntry=FALSE;
+	headerL_t *list;
+        list = (headerL_t *) malloc(sizeof(headerL_t));
+
+        if (checkArMagic(srcFd)==TRUE)
+		arEntry=TRUE;
+	else
+		errorMsg("isnt an ar archive\n");
+
+	if (arEntry==TRUE) { 
+        	while(readArEntry(srcFd, list) == TRUE) {
+			list->next = (headerL_t *) malloc(sizeof(headerL_t));
+        		*list->next = *head;
+			*head = *list;
+
+			/* recursive check for sub-archives */
+			lseek(srcFd, list->size, SEEK_CUR);
+/*			printf("checking for sub headers\n");
+		        if ((subList = getHeaders(srcFd, list->next)) != NULL) {
+				printf("found a sub archive !\n");
+			}
+			else	
+				printf("didnt find a sub header\n"); */
+		}
+	}
+
+        return(head);
 }
 
 /*
- * populate linked list with all ar file entries and offset 
+ * find an entry in the linked list matching the filename
  */
-static int displayEntry(int srcFd, const char filename[16], int funct)
+static headerL_t *findEntry(headerL_t *head, const char *filename)
 {
-	headerL_t *file;
+	while(head->next != NULL) {
+		if (strcmp(filename, head->name)==0) 
+			return(head);
+		head=head->next;
+	}
+	return(NULL);
+}
 
-	if ((file = getSubFileHeader(srcFd, filename)) == NULL)
-		return(FALSE);
+/*
+ * populate linked list with all ar file entries and offset 
+ */
+static int displayEntry(headerL_t *head, int funct)
+{
 	if ((funct & VERBOSE) == VERBOSE) {
-		printf("%s %d/%d %8d %s ", modeString(file->mode), file->uid, file->gid, file->size, timeString(file->mtime));
+		printf("%s %d/%d %8d %s ", modeString(head->mode), head->uid, head->gid, head->size, timeString(head->mtime));
 	}
-	printf("%s\n", file->name);
+	printf("%s\n", head->name);
+	head = head->next;
 	return(TRUE);
 }
 
-static int extractAr(int srcFd, int dstFd, const char filename[16])
+static int extractAr(int srcFd, int dstFd, headerL_t *file)
 {
-        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);	
@@ -160,7 +237,8 @@ extern int ar_main(int argc, char **argv)
 {
         int funct = 0, opt=0;
 	int srcFd=0, dstFd=0;
- 
+ 	headerL_t *header, *entry, *extractList;
+
 	while ((opt = getopt(argc, argv, "ovt:p:x:")) != -1) {
 		switch (opt) {
 		case 'o':
@@ -180,10 +258,6 @@ extern int ar_main(int argc, char **argv)
 				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);
@@ -200,17 +274,38 @@ extern int ar_main(int argc, char **argv)
                 return(FALSE);
         }
 	
-	/* 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]);
+	entry = (headerL_t *) malloc(sizeof(headerL_t));
+	header = (headerL_t *) malloc(sizeof(headerL_t));
+	extractList = (headerL_t *) malloc(sizeof(headerL_t));	
+
+	header = getHeaders(srcFd, header);
+	
+	/* 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 *) malloc(sizeof(headerL_t));
+                        	*entry->next = *extractList;
+                        	*extractList = *entry;
 			}
-			if ( (funct & EXT_TO_STDOUT) == EXT_TO_STDOUT)	
-				extractAr(srcFd, fileno(stdout), argv[optind]);	
-			if ( (funct & DISPLAY) == DISPLAY)
-				displayEntry(srcFd, argv[optind], funct);
+			optind++;
+		}	
+	}
+	else 
+		/* extract everything */
+		extractList = header;
+	
+       while(extractList->next != NULL) {	
+		if ( (funct & EXT_TO_FILE) == EXT_TO_FILE) {
+			dstFd = open(extractList->name, O_WRONLY | O_CREAT);
+			extractAr(srcFd, dstFd, extractList);
 		}
+		if ( (funct & EXT_TO_STDOUT) == EXT_TO_STDOUT)	
+			extractAr(srcFd, fileno(stdout), extractList);	
+		if ( (funct & DISPLAY) == DISPLAY)
+			displayEntry(extractList, funct);
+		extractList=extractList->next;
+	}
 	return (TRUE);
 }