untar changed to allow deb_extract to extract to memory, allows better operation of dpkg-deb -f
diff --git a/libbb/deb_extract.c b/libbb/deb_extract.c
index 0f5a570..b95dfa4 100644
--- a/libbb/deb_extract.c
+++ b/libbb/deb_extract.c
@@ -75,11 +75,24 @@
 	if (function & extract_fsys_tarfile) {
 		copy_file_chunk(uncompressed_file, stdout, -1);
 	} else {
-		untar(uncompressed_file, function, argument);
+		char *output_buffer = NULL;
+		output_buffer = untar(uncompressed_file, stdout, function, argument);
+		if (function & extract_field) {
+			char *field = NULL;
+			int field_length = 0;
+			int field_start = 0;
+			while ((field = read_package_field(&output_buffer[field_start])) != NULL) {
+				field_length = strlen(field);
+				field_start += (field_length + 1);
+				if (strstr(field, argument) == field) {
+					printf("%s\n", field + strlen(argument) + 2);
+				}
+				free(field);
+			}
+		}
 	}
-	/* we are deliberately terminating the child so we can safely ignore this */
-	gz_close(gunzip_pid);
 
+	gz_close(gunzip_pid);
 	fclose(deb_file);
 	fclose(uncompressed_file);
 	free(ared_file);
diff --git a/libbb/libbb.h b/libbb/libbb.h
index 515bf27..569ed93 100644
--- a/libbb/libbb.h
+++ b/libbb/libbb.h
@@ -239,7 +239,9 @@
 	extract_field = 128
 } extract_function_t;
 extern int deb_extract(const char *package_filename, int function, char *target_dir);
-extern int untar(FILE *src_tar_file, const int untar_function, const char *argument);
+extern char *untar(FILE *src_tar_file, FILE *output, const int untar_function, const char *argument);
+extern char *read_text_file_to_buffer(FILE *src_file);
+extern char *read_package_field(const char *package_buffer);
 
 extern int unzip(FILE *l_in_file, FILE *l_out_file);
 extern void gz_close(int gunzip_pid);
diff --git a/libbb/untar.c b/libbb/untar.c
index b768c0b..e70032c 100644
--- a/libbb/untar.c
+++ b/libbb/untar.c
@@ -22,7 +22,7 @@
 #include <unistd.h>
 #include "libbb.h"
 
-extern int untar(FILE *src_tar_file, const int untar_function, const char *argument)
+extern char *untar(FILE *src_tar_file, FILE *output, const int untar_function, const char *argument)
 {
 	typedef struct raw_tar_header {
         char name[100];               /*   0-99 */
@@ -103,13 +103,12 @@
 		}
 
 		if (untar_function & (extract_contents | extract_verbose_extract)) {
-			printf("%s\n", raw_tar_header.name);
+			fprintf(output, "%s\n", raw_tar_header.name);
 		}
 
 		/* extract files */
 		if (untar_function & (extract_extract | extract_verbose_extract | extract_control)) {
-			dir = xmalloc(strlen(raw_tar_header.name) + strlen(argument) + 2);
-			sprintf(dir, "%s/%s", argument, raw_tar_header.name);
+			dir = concat_path_file(argument, raw_tar_header.name);
 			create_path(dir, 0777);
 		}
 
@@ -120,33 +119,27 @@
 				 * supposed to be a directory, and fall through
 				 */
 				if (raw_tar_header.name[strlen(raw_tar_header.name)-1] != '/') {
-					if (untar_function & (extract_extract | extract_verbose_extract | extract_control)) {
-						FILE *dst_file = wfopen(dir, "w");
-						copy_file_chunk(src_tar_file, dst_file, (unsigned long long) size);
-						uncompressed_count += size;
-						fclose(dst_file);
-					}
-					else if (untar_function & extract_info) {
-						if (strstr(raw_tar_header.name, argument) != NULL) {
-							copy_file_chunk(src_tar_file, stdout, (unsigned long long) size);
-							uncompressed_count += size;
-						}
-					}
-					else if (untar_function & extract_field) {
-						if (strstr(raw_tar_header.name, "./control") != NULL) {
-							char *line;
-							while ((line = get_line_from_file(src_tar_file)) != NULL) {
-								uncompressed_count += strlen(line);
-								if (argument == NULL) {
-									printf("%s",line);
-								}
-								else if (strncmp(line, argument, strlen(argument)) == 0) {
-									char *file_ptr;
-									file_ptr = strstr(line, ": ");
-									printf("%s", file_ptr + 2);
-								}
- 							}
-						}
+					switch (untar_function) {
+						case (extract_extract):
+						case (extract_verbose_extract):
+						case (extract_control): {
+								FILE *dst_file = wfopen(dir, "w");
+								copy_file_chunk(src_tar_file, dst_file, (unsigned long long) size);
+								uncompressed_count += size;
+								fclose(dst_file);
+							}
+							break;
+						case (extract_info):
+							if (strstr(raw_tar_header.name, argument) != NULL) {
+								copy_file_chunk(src_tar_file, stdout, (unsigned long long) size);
+								uncompressed_count += size;
+							}
+							break;
+						case (extract_field):
+							if (strstr(raw_tar_header.name, "control") != NULL) {
+								return(read_text_file_to_buffer(src_tar_file));
+							}
+							break;
 					}
 					break;
 				}
@@ -155,7 +148,7 @@
 					if (create_path(dir, mode) != TRUE) {
 						free(dir);
 						perror_msg("%s: Cannot mkdir", raw_tar_header.name); 
-						return(EXIT_FAILURE);
+						return NULL;
 					}
 				}
 				break;
@@ -164,7 +157,7 @@
 					if (link(raw_tar_header.linkname, raw_tar_header.name) < 0) {
 						free(dir);
 						perror_msg("%s: Cannot create hard link to '%s'", raw_tar_header.name, raw_tar_header.linkname); 
-						return(EXIT_FAILURE);
+						return NULL;
 					}
 				}
 				break;
@@ -173,7 +166,7 @@
 					if (symlink(raw_tar_header.linkname, raw_tar_header.name) < 0) {
 						free(dir);
 						perror_msg("%s: Cannot create symlink to '%s'", raw_tar_header.name, raw_tar_header.linkname); 
-						return(EXIT_FAILURE);
+						return NULL;
 					}
 				}
 				break;
@@ -186,7 +179,7 @@
 			default:
 				error_msg("Unknown file type '%c' in tar file", raw_tar_header.typeflag);
 				free(dir);
-				return(EXIT_FAILURE);
+				return NULL;
 		}
 
 		/*
@@ -201,5 +194,5 @@
 
 //		free(dir);
 	}
-	return(EXIT_SUCCESS);
+	return NULL;
 }