1 files changed, 132 insertions, 0 deletions

diff --git a/libbb/extract_archive.c b/libbb/extract_archive.c
new file mode 100644
index 000000000..f22cbb619
--- /dev/null
+++ b/libbb/extract_archive.c
@@ -0,0 +1,132 @@
+/* 
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+#include <utime.h>
+#include "libbb.h"
+
+/* Extract files in the linear linked list 'extract_headers' to either
+ * filesystem, stdout or buffer depending on the value of 'function' which is
+ * described in extract_files.h 
+ *
+ * prefix doesnt have to be just a directory, it may prefix the filename as well.
+ *
+ * e.g. '/var/lib/dpkg/info/dpkg.' will extract all files to the base bath 
+ * '/var/lib/dpkg/info/' and all files/dirs created in that dir will have 
+ * 'dpkg.' as their prefix
+ *
+ * For this reason if prefix does point to a dir then it must end with a
+ * trailing '/' or else the last dir will be assumed to be the file prefix 
+ */
+
+char *extract_archive(FILE *src_stream, FILE *out_stream, file_headers_t *extract_headers, int function, const char *prefix)
+{
+        FILE *dst_stream = NULL;
+        char *full_name = NULL;
+        char *buffer = NULL;
+        size_t uncompressed_count = 0;
+        struct utimbuf t;
+
+        /* find files to extract or display */  
+        while (extract_headers != NULL) {
+                /* prefix doesnt have to be a proper path it may prepend 
+                 * the filename as well */
+                if (prefix != NULL) {
+                        /* strip leading '/' in filename to extract as prefix may not be dir */
+                        char *tmp_str = strchr(extract_headers->name, '/');
+                        if (tmp_str == NULL) {
+                                tmp_str = extract_headers->name;
+                        } else {
+                                tmp_str++;
+                        }
+                        /* Cant use concat_path_file here as prefix might not be a directory */
+                        full_name = xmalloc(strlen(prefix) + strlen(tmp_str) + 1);
+                        strcpy(full_name, prefix);
+                        strcat(full_name, tmp_str);
+                } else {
+                        full_name = extract_headers->name;
+                }
+
+                /* Seek to start of file, have to use fgetc as src_stream may be a pipe
+                 * you cant [lf]seek on pipes */
+                while (uncompressed_count < extract_headers->offset) {
+                        fgetc(src_stream);
+                        uncompressed_count++;
+                }
+
+                if (S_ISREG(extract_headers->mode)) {
+                        if (function & extract_to_stdout) {
+                                copy_file_chunk(src_stream, out_stream, extract_headers->size);                 
+                                uncompressed_count += extract_headers->size;
+                        }
+                        else if (function & extract_all_to_fs) {
+                                dst_stream = wfopen(full_name, "w");
+                                copy_file_chunk(src_stream, dst_stream, extract_headers->size);                 
+                                uncompressed_count += extract_headers->size;
+                                fclose(dst_stream);
+                        }
+                        else if (function & extract_one_to_buffer) {
+                                buffer = (char *) xmalloc(extract_headers->size + 1);
+                                fread(buffer, 1, extract_headers->size, src_stream);
+                                break;
+                        }
+                }
+#if defined BB_DPKG | defined BB_DPKG_DEB 
+                else if (S_ISDIR(extract_headers->mode)) {
+                        if (function & extract_all_to_fs) {
+                                if (create_path(full_name, extract_headers->mode) == FALSE) {
+                                        perror_msg("Cannot mkdir %s", extract_headers->name); 
+                                        return NULL;
+                                }
+                        }
+                }
+                else if (S_ISLNK(extract_headers->mode)) {
+                        if (function & extract_all_to_fs) {
+                                if (symlink(extract_headers->link_name, full_name) < 0) {
+                                        perror_msg("Cannot create hard link from %s to '%s'", extract_headers->name, extract_headers->link_name); 
+                                        return NULL;
+                                }
+                        }
+                }
+#endif
+                if (function & extract_verbose_list) {
+                        fprintf(out_stream, "%s %d/%d %8d %s ", mode_string(extract_headers->mode), 
+                                extract_headers->uid, extract_headers->gid,
+                                (int) extract_headers->size, time_string(extract_headers->mtime));
+                }
+
+                if ((function & extract_list) || (function & extract_verbose_list)){
+                        /* fputs doesnt add a trailing \n, so use fprintf */
+                        fprintf(out_stream, "%s\n", extract_headers->name);
+                }
+
+                if (function & extract_preserve_date) {
+                        t.actime = extract_headers->mtime;
+                        t.modtime = extract_headers->mtime;
+                        utime(full_name, &t);
+                }
+                chmod(full_name, extract_headers->mode);
+                free(full_name);
+
+                extract_headers = extract_headers->next;
+        }
+
+        return(buffer);
+}
+