POSIX GNU tar read support

- supporting tared csm.bin of Chasm: The Rift Remastered at https://store.steampowered.com/app/2061230/Chasm_The_Rift/
- Thanks to @sezero for OS/2 and Windows fixes

Author: Jon Daniel

src/physfs_archiver_tar.c

@@ -17,6 +17,7 @@ static bool TAR_loadEntries(PHYSFS_Io *io, void *arc)
 	union block zero_block;
 	union block current_block;
 	PHYSFS_uint64 count = 0;
+	bool long_name = false;
 
 	memset(zero_block.buffer, 0, sizeof(BLOCKSIZE));
 	memset(current_block.buffer, 0, sizeof(BLOCKSIZE));
@@ -31,7 +32,7 @@ static bool TAR_loadEntries(PHYSFS_Io *io, void *arc)
 		switch(TAR_magic(&current_block))
 		{
 			case POSIX_FORMAT:
-				TAR_posix_block(io, arc, &current_block, &count);
+				TAR_posix_block(io, arc, &current_block, &count, &long_name);
 				break;
 			case OLDGNU_FORMAT:
 				break;

src/physfs_tar.h

@@ -1,15 +1,7 @@
 #ifndef _INCLUDE_PHYSFS_TAR_H_
 #define _INCLUDE_PHYSFS_TAR_H_
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <stdint.h>
 #include <stdbool.h>
-#include <string.h>
-#include <ctype.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <time.h>
 
 #ifndef PATH_MAX
 #define PATH_MAX 1024
@@ -114,43 +106,37 @@ union block
   struct posix_header header;
 };
 
-static PHYSFS_uint64 TAR_decodeOctal(char* data, size_t size) {
-    unsigned char* currentPtr = (unsigned char*) data + size;
+static PHYSFS_uint64 TAR_decodeOctal(char *data, size_t size) {
+    unsigned char *currentPtr = (unsigned char*) data + size;
     PHYSFS_uint64 sum = 0;
     PHYSFS_uint64 currentMultiplier = 1;
-    unsigned char* checkPtr = currentPtr;
+    unsigned char *checkPtr = currentPtr;
 
-    for (; checkPtr >= (unsigned char*) data; checkPtr--) {
+    for (; checkPtr >= (unsigned char *) data; checkPtr--) {
         if ((*checkPtr) == 0 || (*checkPtr) == ' ') {
             currentPtr = checkPtr - 1;
         }
     }
-    for (; currentPtr >= (unsigned char*) data; currentPtr--) {
+    for (; currentPtr >= (unsigned char *) data; currentPtr--) {
         sum += (*currentPtr - 48) * currentMultiplier;
         currentMultiplier *= 8;
     }
     return sum;
 }
 
-static bool TAR_encodeOctal(char* data, size_t size, PHYSFS_uint64 i) {
-    if(	snprintf(data, size, "%llo", i) < 0 )
-    	return false;
-    return true;
-}
-
-static int TAR_magic(union block* block) {
+static enum archive_format TAR_magic(union block *block) {
 	if(strcmp(block->header.magic, OLDGNU_MAGIC) == 0 && strncmp(block->header.version, TVERSION, 2) == 0)
-		return (int)OLDGNU_FORMAT;
+		return OLDGNU_FORMAT;
 	if(strncmp(block->header.magic, TMAGIC, TMAGLEN - 1) == 0)
-		return (int)POSIX_FORMAT;
-	return (int)DEFAULT_FORMAT;
+		return POSIX_FORMAT;
+	return DEFAULT_FORMAT;
 }
 
-static size_t TAR_fileSize(union block* block) {
+static PHYSFS_uint64 TAR_fileSize(union block *block) {
 	return TAR_decodeOctal(block->header.size, sizeof(block->header.size));
 }
 
-static bool TAR_checksum(union block* block) {
+static bool TAR_checksum(union block *block) {
 	PHYSFS_sint64 unsigned_sum = 0;
 	PHYSFS_sint64 signed_sum = 0;
 	PHYSFS_uint64 reference_chksum = 0;
@@ -161,23 +147,23 @@ static bool TAR_checksum(union block* block) {
 	memset(block->header.chksum, ' ', 8);
 
 	for(; i < BLOCKSIZE; i++) {
-		unsigned_sum += ((unsigned char*) block->buffer)[i];
-			signed_sum += ((signed char*) block->buffer)[i];
+		unsigned_sum += ((unsigned char *) block->buffer)[i];
+			signed_sum += ((signed char *) block->buffer)[i];
 	}
 	memcpy(block->header.chksum, orig_chksum, 8);
 	reference_chksum = TAR_decodeOctal(orig_chksum, 12);
 	return (reference_chksum == unsigned_sum || reference_chksum == signed_sum);
 }
 
-time_t TAR_time(union block* block)
+static PHYSFS_uint64 TAR_time(union block *block)
 {
 	return TAR_decodeOctal(block->header.mtime, 12);
 }
 
-bool TAR_posix_block(PHYSFS_Io* io, void* arc, union block* block, PHYSFS_uint64* count)
+static bool TAR_posix_block(PHYSFS_Io *io, void *arc, union block *block, PHYSFS_uint64 *count, bool *long_name)
 {
 	static bool long_name = false;
-	const PHYSFS_Allocator* allocator = PHYSFS_getAllocator();
+	const PHYSFS_Allocator *allocator = PHYSFS_getAllocator();
         char name[PATH_MAX] = { 0 };
 	PHYSFS_sint64 time  = 0;
 	PHYSFS_uint64 size  = 0;
@@ -204,10 +190,10 @@ bool TAR_posix_block(PHYSFS_Io* io, void* arc, union block* block, PHYSFS_uint64
 	/* add file type entry */
 	if (block->header.typeflag == REGTYPE || block->header.typeflag == 0) {
 		/* support long file names */
-		if(long_name) {
+		if(*long_name) {
 			strcpy(&name[0], block->header.name);
 			BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, block->buffer, BLOCKSIZE), 0);
-			long_name = false;
+			*long_name = false;
 			(*count)++;
 		}
 		size = TAR_fileSize(block);
@@ -228,7 +214,7 @@ bool TAR_posix_block(PHYSFS_Io* io, void* arc, union block* block, PHYSFS_uint64
 	/* long name mode */
 	else if(block->header.typeflag == GNUTYPE_LONGNAME)
 	{
-		long_name = true;
+		*long_name = true;
 	}
 	else
 	{