find: implement -empty

function                                             old     new   delta
func_empty                                             -     121    +121
packed_usage                                       33154   33167     +13
parse_params                                        1490    1500     +10
static.params                                        228     235      +7
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 3/0 up/down: 151/0)             Total: 151 bytes

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/findutils/find.c b/findutils/find.c
index d6679bd0835f4497f91b4ede9c6958bf9e9b04aa..9a2c61b757329187b407fbb932485548e2d940f6 100644 (file)
--- a/findutils/find.c
+++ b/findutils/find.c
@@ -203,6 +203,14 @@
 //config:      WARNING: This option can do much harm if used wrong. Busybox will not
 //config:      try to protect the user from doing stupid things. Use with care.
 //config:
+//config:config FEATURE_FIND_EMPTY
+//config:      bool "Enable -empty: match empty files or directories"
+//config:      default y
+//config:      depends on FIND
+//config:      help
+//config:      Support the 'find -empty' option to find empty regular files
+//config:      or directories.
+//config:
 //config:config FEATURE_FIND_PATH
 //config:      bool "Enable -path: match pathname with shell pattern"
 //config:      default y
@@ -315,6 +323,9 @@
 //usage:       IF_FEATURE_FIND_CONTEXT(
 //usage:     "\n       -context CTX    File has specified security context"
 //usage:       )
+//usage:       IF_FEATURE_FIND_EMPTY(
+//usage:     "\n       -empty          Match empty file/directory"
+//usage:       )
 //usage:       IF_FEATURE_FIND_PRUNE(
 //usage:     "\n       -prune          If current file is directory, don't descend into it"
 //usage:       )
@@ -396,6 +407,7 @@ IF_FEATURE_FIND_PAREN(  ACTS(paren, action ***subexpr;))
 IF_FEATURE_FIND_PRUNE(  ACTS(prune))
 IF_FEATURE_FIND_QUIT(   ACTS(quit))
 IF_FEATURE_FIND_DELETE( ACTS(delete))
+IF_FEATURE_FIND_EMPTY(  ACTS(empty))
 IF_FEATURE_FIND_EXEC(   ACTS(exec,
                                char **exec_argv; /* -exec ARGS */
                                unsigned *subst_count;
@@ -824,6 +836,30 @@ ACTF(delete)
        return TRUE;
 }
 #endif
+#if ENABLE_FEATURE_FIND_EMPTY
+ACTF(empty)
+{
+       if (S_ISDIR(statbuf->st_mode)) {
+               DIR *dir;
+               struct dirent *dent;
+
+               dir = opendir(fileName);
+               if (!dir) {
+                       bb_simple_perror_msg(fileName);
+                       return FALSE;
+               }
+
+               while ((dent = readdir(dir)) != NULL
+                && DOT_OR_DOTDOT(dent->d_name)
+               ) {
+                       continue;
+               }
+               closedir(dir);
+               return dent == NULL;
+       }
+       return S_ISREG(statbuf->st_mode) && statbuf->st_size == 0;
+}
+#endif
 #if ENABLE_FEATURE_FIND_CONTEXT
 ACTF(context)
 {
@@ -989,6 +1025,7 @@ static action*** parse_params(char **argv)
        IF_FEATURE_FIND_PRUNE(  PARM_prune     ,)
        IF_FEATURE_FIND_QUIT(   PARM_quit      ,)
        IF_FEATURE_FIND_DELETE( PARM_delete    ,)
+       IF_FEATURE_FIND_EMPTY(  PARM_empty     ,)
        IF_FEATURE_FIND_EXEC(   PARM_exec      ,)
        IF_FEATURE_FIND_EXECUTABLE(PARM_executable,)
        IF_FEATURE_FIND_PAREN(  PARM_char_brace,)
@@ -1034,6 +1071,7 @@ static action*** parse_params(char **argv)
        IF_FEATURE_FIND_PRUNE(  "-prune\0"  )
        IF_FEATURE_FIND_QUIT(   "-quit\0"  )
        IF_FEATURE_FIND_DELETE( "-delete\0" )
+       IF_FEATURE_FIND_EMPTY(  "-empty\0"  )
        IF_FEATURE_FIND_EXEC(   "-exec\0"   )
        IF_FEATURE_FIND_EXECUTABLE("-executable\0")
        IF_FEATURE_FIND_PAREN(  "(\0"       )
@@ -1203,6 +1241,12 @@ static action*** parse_params(char **argv)
                        (void) ALLOC_ACTION(delete);
                }
 #endif
+#if ENABLE_FEATURE_FIND_EMPTY
+               else if (parm == PARM_empty) {
+                       dbg("%d", __LINE__);
+                       (void) ALLOC_ACTION(empty);
+               }
+#endif
 #if ENABLE_FEATURE_FIND_EXEC
                else if (parm == PARM_exec) {
                        int i;