unzip: implement -j, closes 9126

function                                             old     new   delta
unzip_main                                          2642    2703     +61
packed_usage                                       31747   31770     +23
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 84/0)               Total: 84 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 30 insertions, 16 deletions

diff --git a/archival/unzip.c b/archival/unzip.c
index 21ba172b5..d5bca08d4 100644
--- a/archival/unzip.c
+++ b/archival/unzip.c
@@ -62,6 +62,7 @@
 //usage:     "\n        -l      List contents (with -q for short form)"
 //usage:     "\n        -n      Never overwrite files (default: ask)"
 //usage:     "\n        -o      Overwrite"
+//usage:     "\n        -j      Do not restore paths"
 //usage:     "\n        -p      Print to stdout"
 //usage:     "\n        -q      Quiet"
 //usage:     "\n        -x FILE Exclude FILEs"
@@ -455,13 +456,16 @@ static int get_lstat_mode(const char *dst_fn)
 int unzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int unzip_main(int argc, char **argv)
 {
-        enum { O_PROMPT, O_NEVER, O_ALWAYS };
-
+        enum {
+                OPT_l = (1 << 0),
+                OPT_x = (1 << 1),
+                OPT_j = (1 << 2),
+        };
+        unsigned opts;
         smallint quiet = 0;
         IF_NOT_FEATURE_UNZIP_CDF(const) smallint verbose = 0;
-        smallint listing = 0;
+        enum { O_PROMPT, O_NEVER, O_ALWAYS };
         smallint overwrite = O_PROMPT;
-        smallint x_opt_seen;
         uint32_t cdf_offset;
         unsigned long total_usize;
         unsigned long total_size;
@@ -472,7 +476,7 @@ int unzip_main(int argc, char **argv)
         llist_t *zaccept = NULL;
         llist_t *zreject = NULL;
         char *base_dir = NULL;
-        int i, opt;
+        int i;
         char key_buf[80]; /* must match size used by my_fgets80 */
 
 /* -q, -l and -v: UnZip 5.52 of 28 February 2005, by Info-ZIP:
@@ -516,16 +520,16 @@ int unzip_main(int argc, char **argv)
  *    204372                   1 file
  */
 
-        x_opt_seen = 0;
+        opts = 0;
         /* '-' makes getopt return 1 for non-options */
-        while ((opt = getopt(argc, argv, "-d:lnopqxv")) != -1) {
-                switch (opt) {
+        while ((i = getopt(argc, argv, "-d:lnopqxjv")) != -1) {
+                switch (i) {
                 case 'd':  /* Extract to base directory */
                         base_dir = optarg;
                         break;
 
                 case 'l': /* List */
-                        listing = 1;
+                        opts |= OPT_l;
                         break;
 
                 case 'n': /* Never overwrite existing files */
@@ -545,11 +549,15 @@ int unzip_main(int argc, char **argv)
 
                 case 'v': /* Verbose list */
                         IF_FEATURE_UNZIP_CDF(verbose++;)
-                        listing = 1;
+                        opts |= OPT_l;
                         break;
 
                 case 'x':
-                        x_opt_seen = 1;
+                        opts |= OPT_x;
+                        break;
+
+                case 'j':
+                        opts |= OPT_j;
                         break;
 
                 case 1:
@@ -558,7 +566,7 @@ int unzip_main(int argc, char **argv)
                                 /* +5: space for ".zip" and NUL */
                                 src_fn = xmalloc(strlen(optarg) + 5);
                                 strcpy(src_fn, optarg);
-                        } else if (!x_opt_seen) {
+                        } else if (!(opts & OPT_x)) {
                                 /* Include files */
                                 llist_add_to(&zaccept, optarg);
                         } else {
@@ -626,7 +634,7 @@ int unzip_main(int argc, char **argv)
         if (quiet <= 1) { /* not -qq */
                 if (quiet == 0)
                         printf("Archive:  %s\n", src_fn);
-                if (listing) {
+                if (opts & OPT_l) {
                         puts(verbose ?
                                 " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
                                 "--------  ------  ------- ---- ---------- ----- --------  ----"
@@ -778,13 +786,19 @@ int unzip_main(int argc, char **argv)
                 free(dst_fn);
                 dst_fn = xzalloc(zip.fmt.filename_len + 1);
                 xread(zip_fd, dst_fn, zip.fmt.filename_len);
-
                 /* Skip extra header bytes */
                 unzip_skip(zip.fmt.extra_len);
 
                 /* Guard against "/abspath", "/../" and similar attacks */
                 overlapping_strcpy(dst_fn, strip_unsafe_prefix(dst_fn));
 
+                if (opts & OPT_j) /* Strip paths? */
+                        overlapping_strcpy(dst_fn, bb_basename(dst_fn));
+
+                /* Did this strip everything ("DIR/" case)? Then skip */
+                if (!dst_fn[0])
+                        goto skip_cmpsize;
+
                 /* Filter zip entries */
                 if (find_list_entry(zreject, dst_fn)
                  || (zaccept && !find_list_entry(zaccept, dst_fn))
@@ -792,7 +806,7 @@ int unzip_main(int argc, char **argv)
                         goto skip_cmpsize;
                 }
 
-                if (listing) {
+                if (opts & OPT_l) {
                         /* List entry */
                         char dtbuf[sizeof("mm-dd-yyyy hh:mm")];
                         sprintf(dtbuf, "%02u-%02u-%04u %02u:%02u",
@@ -960,7 +974,7 @@ int unzip_main(int argc, char **argv)
                 total_entries++;
         }
 
-        if (listing && quiet <= 1) {
+        if ((opts & OPT_l) && quiet <= 1) {
                 if (!verbose) {
                         //      "  Length      Date    Time    Name\n"
                         //      "---------  ---------- -----   ----"