bb_mkdep release. speed up *3, clearing, more comments

git-svn-id: svn://busybox.net/trunk/busybox@11446 69ca8d6d-28ef-0310-b511-8ec308f3f277

2 files changed, 267 insertions, 219 deletions

diff --git a/scripts/.cvsignore b/scripts/.cvsignore
index 07fa550f5..b1ebf606d 100644
--- a/scripts/.cvsignore
+++ b/scripts/.cvsignore
@@ -1,2 +1 @@
-mkdep
-split-include
+bb_mkdep
diff --git a/scripts/bb_mkdep.c b/scripts/bb_mkdep.c
index 68b3f5bce..ee8456778 100644
--- a/scripts/bb_mkdep.c
+++ b/scripts/bb_mkdep.c
@@ -1,5 +1,5 @@
 /*
- * Another dependences for Makefile mashine generator
+ * Another dependences for Makefile fast mashine generator
  *
  * Copyright (C) 2005 by Vladimir Oleynik <dzo@simtreas.ru>
  *
@@ -19,6 +19,7 @@
  * -w                     (show warning if include files not found)
  * -k include/config      (default: INCLUDE_CONFIG_PATH)
  * -c include/config.h    (configs, default: INCLUDE_CONFIG_KEYS_PATH)
+ * dirs_for_scan          (default ".")
 */
 
 #define LOCAL_INCLUDE_PATH          "include"
@@ -47,9 +48,13 @@ typedef struct BB_KEYS {
         struct BB_KEYS *next;
 } bb_key_t;
 
+typedef struct FILE_LIST {
+        char *name;
+        char *ext;      /* *.c or *.h, point to last char */
+        long size;
+} file_list_t;
 
 /* partial and simplify libbb routine */
-
 static void bb_error_d(const char *s, ...) __attribute__ ((noreturn, format (printf, 1, 2)));
 static char * bb_asprint(const char *format, ...) __attribute__ ((format (printf, 1, 2)));
 
@@ -66,15 +71,20 @@ static char *bb_simplify_path(const char *path);
 
 /* for lexical analyzier */
 static bb_key_t *key_top;
+static llist_t *configs;
 
 static void parse_inc(const char *include, const char *fname);
 static void parse_conf_opt(char *opt, const char *val, size_t rsz);
 
-static char first_char_conf_opts[256];  /* for speed */
+/* for speed triks */
+static char first_chars[257];  /* + L_EOF */
 
-#define CHECK_ONLY  0
-#define MAKE_NEW    1
-static bb_key_t *find_already(bb_key_t *k, const char *nk, int flg_save_new);
+static int pagesizem1;
+static size_t mema_id = 128;   /* first allocated for id */
+static char *id_s;
+
+static bb_key_t *check_key(bb_key_t *k, const char *nk);
+static bb_key_t *make_new_key(bb_key_t *k, const char *nk);
 
 #define yy_error_d(s) bb_error_d("%s:%d hmm, %s", fname, line, s)
 
@@ -82,40 +92,41 @@ static bb_key_t *find_already(bb_key_t *k, const char *nk, int flg_save_new);
 #define S      0        /* start state */
 #define STR    '"'      /* string */
 #define CHR    '\''     /* char */
-#define REM    '*'      /* block comment */
+#define REM    '/'      /* block comment */
+#define BS     '\\'     /* back slash */
 #define POUND  '#'      /* # */
 #define I      'i'      /* #include preprocessor`s directive */
 #define D      'd'      /* #define preprocessor`s directive */
 #define U      'u'      /* #undef preprocessor`s directive */
 #define LI     'I'      /* #include "... */
 #define DK     'K'      /* #define KEY... (config mode) */
-#define DV     'V'      /* #define KEY "... or #define KEY '... */
-#define NLC    'n'      /* \+\n */
-#define ANY    '?'      /* skip unparsed . */
+#define DV     'V'      /* #define KEY "VALUE or #define KEY 'VALUE */
+#define NLC    'n'      /* \ and \n */
+#define ANY    '*'      /* any unparsed chars */
 
+#define L_EOF  256
 /* [A-Z_a-z] */
 #define ID(c) ((c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z') || c == '_')
 /* [A-Z_a-z0-9] */
 #define ISALNUM(c)  (ID(c) || (c >= '0' && c <= '9'))
 
-#define getc1()     do { c = (optr >= oend) ? EOF : *optr++; } while(0)
+#define getc1()     do { c = (optr >= oend) ? L_EOF : *optr++; } while(0)
 #define ungetc1()   optr--
 
-#define put_id(c)   do {    if(id_len == mema_id)                 \
-                                id = xrealloc(id, mema_id += 16); \
+#define put_id(c)   do {    if(id_len == local_mema_id)                 \
+                                id = xrealloc(id, local_mema_id += 16); \
                             id[id_len++] = c; } while(0)
 
 /* stupid C lexical analizator */
-static void c_lex(const char *fname, int flg_config_include)
+static void c_lex(const char *fname, long fsize)
 {
-  int c = EOF;                      /* stupid initialize */
-  int prev_state = EOF;
+  int c = L_EOF;                     /* stupid initialize */
+  int prev_state = L_EOF;
   int called;
   int state;
   int line;
-  static size_t mema_id;
-  static char *id_s;
-  char *id;
+  char *id = id_s;
+  size_t local_mema_id = mema_id;
   size_t id_len = 0;                /* stupid initialize */
   char *val = NULL;
   unsigned char *optr, *oend;
@@ -124,35 +135,20 @@ static void c_lex(const char *fname, int flg_config_include)
   int fd;
   char *map;
   int mapsize;
-  {
-    /* stolen from mkdep by Linus Torvalds */
-    int pagesizem1 = getpagesize() - 1;
-    struct stat st;
 
-    fd = open(fname, O_RDONLY);
-    if(fd < 0) {
+  fd = open(fname, O_RDONLY);
+  if(fd < 0) {
         perror(fname);
         return;
-    }
-    fstat(fd, &st);
-    if (st.st_size == 0)
-        bb_error_d("%s is empty", fname);
-    mapsize = st.st_size;
-    mapsize = (mapsize+pagesizem1) & ~pagesizem1;
-    map = mmap(NULL, mapsize, PROT_READ, MAP_PRIVATE, fd, 0);
-    if ((long) map == -1)
+  }
+  mapsize = (fsize+pagesizem1) & ~pagesizem1;
+  map = mmap(NULL, mapsize, PROT_READ, MAP_PRIVATE, fd, 0);
+  if ((long) map == -1)
         bb_error_d("%s: mmap: %m", fname);
 
-    /* hereinafter is my */
-    optr = (unsigned char *)map;
-    oend = optr + st.st_size;
-  }
+  optr = (unsigned char *)map;
+  oend = optr + fsize;
 
-  if(id_s == NULL) {
-    /* fist allocate */
-    id_s = xmalloc(mema_id=128);
-  }
-  id = id_s;
   line = 1;
   called = state = S;
 
@@ -163,10 +159,7 @@ static void c_lex(const char *fname, int flg_config_include)
             if(state == LI) {
                 parse_inc(id, fname);
             } else {
-                /*
-                if(val[0] == '\0')
-                    yy_error_d("expected value");
-                */
+                /* #define KEY "[VAL]" */
                 parse_conf_opt(id, val, (optr - start));
             }
             state = S;
@@ -180,7 +173,7 @@ static void c_lex(const char *fname, int flg_config_include)
         while(c == ' ' || c == '\t')
             getc1();
 
-        if(c == '\\') {
+        if(c == BS) {
                 getc1();
                 if(c == '\n') {
                         /* \\\n eat continued */
@@ -189,49 +182,50 @@ static void c_lex(const char *fname, int flg_config_include)
                         continue;
                 }
                 ungetc1();
-                c = '\\';
+                c = BS;
         }
 
         if(state == S) {
-                while(c <= ' ' && c != EOF) {
-                    /* <S>[\000- ]+ */
+                while(first_chars[c] == ANY) {
+                    /* <S>unparsed */
                     if(c == '\n')
                         line++;
                     getc1();
                 }
-                if(c == EOF) {
+                if(c == L_EOF) {
                         /* <S><<EOF>> */
+                        id_s = id;
+                        mema_id = local_mema_id;
                         munmap(map, mapsize);
                         close(fd);
                         return;
                 }
-                if(c == '/') {
+                if(c == REM) {
                         /* <S>/ */
-                        getc1();
-                        if(c == '/') {
+                        getc1();    /* eat <S>/ */
+                        if(c == REM) {
                                 /* <S>"//"[^\n]* */
-                                do getc1(); while(c != '\n' && c != EOF);
+                                do getc1(); while(c != '\n' && c != L_EOF);
                         } else if(c == '*') {
                                 /* <S>[/][*] */
                                 called = S;
                                 state = REM;
                         }
-                        /* eat <S>/ */
-                } else if(c == '#') {
-                        /* <S>\"|\'|# */
+                } else if(c == POUND) {
+                        /* <S># */
                         start = optr - 1;
                         state = c;
                 } else if(c == STR || c == CHR) {
-                        /* <S>\"|\'|# */
+                        /* <S>\"|\' */
                         val = NULL;
                         called = S;
                         state = c;
-                } else if(ISALNUM(c)) {
+                } else if(c != BS) {
                         /* <S>[A-Z_a-z0-9] */
 
                         /* trick for fast drop id
                            if key with this first char undefined */
-                        if(first_char_conf_opts[c] == 0) {
+                        if(first_chars[c] == 0) {
                             /* skip <S>[A-Z_a-z0-9]+ */
                             do getc1(); while(ISALNUM(c));
                         } else {
@@ -242,11 +236,11 @@ static void c_lex(const char *fname, int flg_config_include)
                                 getc1();
                             } while(ISALNUM(c));
                             put_id(0);
-                            find_already(key_top, id, CHECK_ONLY);
+                            check_key(key_top, id);
                         }
                 } else {
-                    /* <S>. */
-                    prev_state = ANY;
+                    /* <S>\\ */
+                    prev_state = c;
                 }
                 continue;
         }
@@ -259,13 +253,13 @@ static void c_lex(const char *fname, int flg_config_include)
                                 if(called != S)
                                     yy_error_d("unexpected newline");
                                 line++;
-                        } else if(c == EOF)
+                        } else if(c == L_EOF)
                                 yy_error_d("unexpected EOF");
                         getc1();
                 }
                 /* <REM>[*] */
                 getc1();
-                if(c == '/') {
+                if(c == REM) {
                         /* <REM>[*][/] */
                         state = called;
                         break;
@@ -276,14 +270,14 @@ static void c_lex(const char *fname, int flg_config_include)
         if(state == STR || state == CHR) {
             for(;;) {
                 /* <STR,CHR>\n|<<EOF>> */
-                if(c == '\n' || c == EOF)
+                if(c == '\n' || c == L_EOF)
                         yy_error_d("unterminating");
-                if(c == '\\') {
+                if(c == BS) {
                         /* <STR,CHR>\\ */
                         getc1();
-                        if(c != '\\' && c != '\n' && c != state) {
+                        if(c != BS && c != '\n' && c != state) {
                             /* another usage \ in str or char */
-                            if(c == EOF)
+                            if(c == L_EOF)
                                 yy_error_d("unexpected EOF");
                             if(val)
                                 put_id(c);
@@ -298,7 +292,7 @@ static void c_lex(const char *fname, int flg_config_include)
                 } else if(c == state) {
                         /* <STR>\" or <CHR>\' */
                         if(called == DV)
-                            put_id(c);
+                            put_id(c);  /* #define KEY "VALUE"<- */
                         state = called;
                         break;
                 } else if(val)
@@ -310,12 +304,12 @@ static void c_lex(const char *fname, int flg_config_include)
         }
 
         /* begin preprocessor states */
-        if(c == EOF)
+        if(c == L_EOF)
             yy_error_d("unexpected EOF");
-        if(c == '/') {
+        if(c == REM) {
                 /* <#.*>/ */
                 getc1();
-                if(c == '/')
+                if(c == REM)
                         yy_error_d("detect // in preprocessor line");
                 if(c == '*') {
                         /* <#.*>[/][*] */
@@ -326,51 +320,55 @@ static void c_lex(const char *fname, int flg_config_include)
                 /* hmm, #.*[/] */
                 yy_error_d("strange preprocessor line");
         }
-        if(state == '#') {
+        if(state == POUND) {
+            if(c != 'd' && c != 'u' && c != 'i') {
+                while(ISALNUM(c))
+                    getc1();
+                state = S;
+            } else {
                 static const char * const preproc[] = {
                     "define", "undef", "include", ""
                 };
                 const char * const *str_type;
 
                 id_len = 0;
-                while(ISALNUM(c)) {
-                    put_id(c);
-                    getc1();
-                }
+                do { put_id(c); getc1(); } while(ISALNUM(c));
                 put_id(0);
                 for(str_type = preproc; (state = **str_type); str_type++) {
                     if(*id == state && strcmp(id, *str_type) == 0)
                         break;
                 }
                 /* to S if another #directive */
-                ungetc1();
                 id_len = 0; /* common for save */
-                continue;
+            }
+            ungetc1();
+            continue;
         }
         if(state == I) {
                 if(c == STR) {
                         /* <I>\" */
                         val = id;
-                        state = STR;
                         called = LI;
-                        continue;
+                        state = STR;
+                } else {
+                    /* another (may be wrong) #include ... */
+                    ungetc1();
+                    state = S;
                 }
-                /* another (may be wrong) #include ... */
-                ungetc1();
-                state = S;
                 continue;
         }
         if(state == D || state == U) {
-            while(ISALNUM(c)) {
-                if(flg_config_include) {
-                    /* save KEY from #"define"|"undef" ... */
-                    put_id(c);
-                }
-                getc1();
-            }
-            if(!flg_config_include) {
+            if(configs == NULL) {
+                /* ignore depend with #define or #undef KEY */
+                while(ISALNUM(c))
+                    getc1();
                 state = S;
             } else {
+                /* save KEY from #"define"|"undef" ... */
+                while(ISALNUM(c)) {
+                    put_id(c);
+                    getc1();
+                }
                 if(!id_len)
                     yy_error_d("expected identificator");
                 put_id(0);
@@ -386,7 +384,7 @@ static void c_lex(const char *fname, int flg_config_include)
             continue;
         }
         if(state == DK) {
-            /* #define (config mode) */
+            /* #define KEY[ ] (config mode) */
             val = id + id_len;
             if(c == STR || c == CHR) {
                 /* define KEY "... or define KEY '... */
@@ -396,6 +394,7 @@ static void c_lex(const char *fname, int flg_config_include)
                 continue;
             }
             while(ISALNUM(c)) {
+                /* VALUE */
                 put_id(c);
                 getc1();
             }
@@ -410,43 +409,51 @@ static void c_lex(const char *fname, int flg_config_include)
 static void show_usage(void) __attribute__ ((noreturn));
 static void show_usage(void)
 {
-        bb_error_d("Usage: [-I local_include_path] [-dw] "
-                        "[-k path_for_store_keys] [-s skip_file]");
+        bb_error_d("Usage: [-I local_include_paths] [-dw] "
+                   "[-k path_for_store_keys] [-s skip_file] [dirs]");
 }
 
 static const char *kp;
+static size_t kp_len;
 static llist_t *Iop;
 static bb_key_t *Ifound;
 static int noiwarning;
-static llist_t *configs;
 
-static bb_key_t *find_already(bb_key_t *k, const char *nk, int flg_save_new)
+static bb_key_t *check_key(bb_key_t *k, const char *nk)
 {
-        bb_key_t *cur;
+    bb_key_t *cur;
 
-        for(cur = k; cur; cur = cur->next) {
-            if(strcmp(cur->keyname, nk) == 0) {
-                cur->checked = 1;
-                return NULL;
-            }
+    for(cur = k; cur; cur = cur->next) {
+        if(strcmp(cur->keyname, nk) == 0) {
+            cur->checked = 1;
+            return cur;
         }
-        if(flg_save_new == CHECK_ONLY)
-            return NULL;
-        cur = xmalloc(sizeof(bb_key_t));
-        cur->keyname = bb_xstrdup(nk);
+    }
+    return NULL;
+}
+
+static bb_key_t *make_new_key(bb_key_t *k, const char *nk)
+{
+        bb_key_t *cur;
+        size_t nk_size;
+
+        nk_size = strlen(nk) + 1;
+        cur = xmalloc(sizeof(bb_key_t) + nk_size);
+        cur->keyname = memcpy(cur + 1, nk, nk_size);
         cur->checked = 1;
         cur->next = k;
         return cur;
 }
 
-static int store_include_fullpath(char *p_i, bb_key_t *li)
+static inline char *store_include_fullpath(char *p_i, bb_key_t *li)
 {
     struct stat st;
-    int ok = 0;
+    char *ok;
 
     if(stat(p_i, &st) == 0) {
-        li->stored_path = bb_simplify_path(p_i);
-        ok = 1;
+        ok = li->stored_path = bb_simplify_path(p_i);
+    } else {
+        ok = NULL;
     }
     free(p_i);
     return ok;
@@ -458,9 +465,11 @@ static void parse_inc(const char *include, const char *fname)
         char *p_i;
         llist_t *lo;
 
-        if((li = find_already(Ifound, include, MAKE_NEW)) == NULL)
+        li = check_key(Ifound, include);
+        if(li)
             return;
-        Ifound = li;
+        Ifound = li = make_new_key(Ifound, include);
+
         if(include[0] != '/') {
             /* relative */
             int w;
@@ -490,9 +499,10 @@ static void parse_inc(const char *include, const char *fname)
 
 static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
 {
-        bb_key_t *cur = find_already(key_top, opt, MAKE_NEW);
+        bb_key_t *cur;
 
-        if(cur != NULL) {
+        cur = check_key(key_top, opt);
+        if(cur == NULL) {
             /* new key, check old key if present after previous usage */
             char *s, *p;
             struct stat st;
@@ -501,6 +511,9 @@ static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
             static char *record_buf;
             static char *r_cmp;
             static size_t r_sz;
+            ssize_t rw_ret;
+
+            cur = make_new_key(key_top, opt);
 
             recordsz += 2;  /* \n\0 */
             if(recordsz > r_sz) {
@@ -509,12 +522,24 @@ static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
             }
             s = record_buf;
             /* may be short count " " */
-            if(val)
-                recordsz = sprintf(s, "#define %s%s%s\n", opt, (*val ? " " : ""), val);
-            else
+            if(val) {
+                if(*val == '\0') {
+                    cur->value = "";
+                    recordsz = sprintf(s, "#define %s\n", opt);
+                } else {
+                    cur->value = bb_xstrdup(val);
+                    recordsz = sprintf(s, "#define %s %s\n", opt, val);
+                }
+            } else {
+                cur->value = NULL;
                 recordsz = sprintf(s, "#undef %s\n", opt);
-            first_char_conf_opts[((int)((unsigned char)(*opt)))] = *opt;
-            /* key converting [A-Z] -> [a-z] */
+            }
+            /* size_t -> ssize_t :( */
+            rw_ret = (ssize_t)recordsz;
+            /* trick, save first char KEY for do fast identify id */
+            first_chars[(int)*opt] = *opt;
+
+            /* key converting [A-Z_] -> [a-z/] */
             for(p = opt; *p; p++) {
                 if(*p >= 'A' && *p <= 'Z')
                         *p = *p - 'A' + 'a';
@@ -524,6 +549,7 @@ static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
             p = bb_asprint("%s/%s.h", kp, opt);
             cur->stored_path = opt = p;
             if(stat(opt, &st)) {
+                p += kp_len;
                 while(*++p) {
                     /* Auto-create directories. */
                     if (*p == '/') {
@@ -535,9 +561,9 @@ static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
                 }
             } else {
                     /* found */
-                    if(st.st_size == recordsz) {
+                    if(st.st_size == (off_t)recordsz) {
                         fd = open(opt, O_RDONLY);
-                        if(fd < 0 || read(fd, r_cmp, recordsz) != recordsz)
+                        if(fd < 0 || read(fd, r_cmp, recordsz) < rw_ret)
                             bb_error_d("%s: %m", opt);
                         close(fd);
                         cmp_ok = memcmp(s, r_cmp, recordsz) == 0;
@@ -545,57 +571,30 @@ static void parse_conf_opt(char *opt, const char *val, size_t recordsz)
             }
             if(!cmp_ok) {
                 fd = open(opt, O_WRONLY|O_CREAT|O_TRUNC, 0644);
-                if(fd < 0 || write(fd, s, recordsz) != recordsz)
+                if(fd < 0 || write(fd, s, recordsz) < rw_ret)
                     bb_error_d("%s: %m", opt);
                 close(fd);
             }
-            /* store only */
-            cur->checked = 0;
-            if(val) {
-                if(*val == '\0') {
-                    cur->value = "";
-                } else {
-                    cur->value = bb_xstrdup(val);
-                }
-            } else {
-                cur->value = NULL;
-            }
             key_top = cur;
         } else {
             /* present already */
-            for(cur = key_top; cur; cur = cur->next) {
-                if(strcmp(cur->keyname, opt) == 0) {
-                    cur->checked = 0;
-                    if(cur->value == NULL && val == NULL)
-                        return;
-                    if((cur->value == NULL && val != NULL) ||
-                            (cur->value != NULL && val == NULL) ||
-                            strcmp(cur->value, val))
-                        fprintf(stderr, "Warning: redefined %s\n", opt);
-                    return;
-                }
-            }
+            if((cur->value == NULL && val != NULL) ||
+               (cur->value != NULL && val == NULL) ||
+               (cur->value != NULL && val != NULL && strcmp(cur->value, val)))
+                    fprintf(stderr, "Warning: redefined %s\n", opt);
         }
+        /* store only */
+        cur->checked = 0;
 }
 
-static int show_dep(int first, bb_key_t *k, const char *a)
+static int show_dep(int first, bb_key_t *k, const char *name)
 {
     bb_key_t *cur;
 
     for(cur = k; cur; cur = cur->next) {
         if(cur->checked && cur->stored_path) {
             if(first) {
-                const char *ext;
-
-                if(*a == '.' && a[1] == '/')
-                    a += 2;
-                ext = strrchr(a, '.');
-                if(ext && ext[1] == 'c' && ext[2] == '\0') {
-                    /* *.c -> *.o */
-                    printf("\n%.*s.o:", (ext - a), a);
-                } else {
-                    printf("\n%s:", a);
-                }
+                printf("\n%s:", name);
                 first = 0;
             } else {
                 printf(" \\\n  ");
@@ -608,50 +607,56 @@ static int show_dep(int first, bb_key_t *k, const char *a)
 }
 
 static llist_t *files;
+static struct stat st_kp;
+
+static char *dir_and_entry;
 
-static llist_t *filter_chd(const char *fe, const char *p, llist_t *pdirs)
+static char *
+filter_chd(const char *fe, const char *p, size_t dirlen)
 {
     struct stat st;
     char *fp;
     char *afp;
     llist_t *cfl;
-    static struct stat st_kp;
+    file_list_t *f;
+    size_t df_sz;
+    static size_t dir_and_entry_sz;
 
     if (*fe == '.')
         return NULL;
-    fp = bb_asprint("%s/%s", p, fe);
+
+    df_sz = dirlen + strlen(fe) + 2;     /* dir/file\0 */
+    if(df_sz > dir_and_entry_sz)
+        dir_and_entry = xrealloc(dir_and_entry, dir_and_entry_sz = df_sz);
+    fp = dir_and_entry;
+    sprintf(fp, "%s/%s", p, fe);
+
     if(stat(fp, &st)) {
         fprintf(stderr, "Warning: stat(%s): %m", fp);
-        free(fp);
         return NULL;
     }
     if(S_ISREG(st.st_mode)) {
-        const char *e = strrchr(fe, '.');
-
-        if(e == NULL || !((e[1]=='c' || e[1]=='h') && e[2]=='\0')) {
+        afp = fp + df_sz - 3;
+        if(*afp++ != '.' || (*afp != 'c' && *afp != 'h')) {
             /* direntry is regular file, but is not *.[ch] */
-            free(fp);
             return NULL;
         }
-    } else {
-        if(st_kp.st_ino == 0) {
-            /* first call */
-            if(stat(kp, &st_kp))
-                bb_error_d("stat(%s): %m", kp);
-            if(!S_ISDIR(st_kp.st_mode))
-                bb_error_d("%s is not directory", kp);
+        if (st.st_size == 0) {
+            fprintf(stderr, "Warning: %s is empty\n", fp);
+            return NULL;
         }
+    } else {
         if(S_ISDIR(st.st_mode)) {
             if (st.st_dev == st_kp.st_dev && st.st_ino == st_kp.st_ino) {
-                /* is autogenerated to kp/key* by previous usage */
-                free(fp);
                 /* drop scan kp/ directory */
                 return NULL;
             }
-            return llist_add_to(pdirs, fp);
+            /* buff is returned, begin of zero allocate */
+            dir_and_entry = NULL;
+            dir_and_entry_sz = 0;
+            return fp;
         }
         /* hmm, is device! */
-        free(fp);
         return NULL;
     }
     afp = bb_simplify_path(fp);
@@ -659,16 +664,18 @@ static llist_t *filter_chd(const char *fe, const char *p, llist_t *pdirs)
         if(cfl->data && strcmp(cfl->data, afp) == 0) {
                 /* parse configs.h */
                 free(afp);
-                c_lex(fp, 1);
-                free(fp);
+                c_lex(fp, st.st_size);
                 free(cfl->data);
                 cfl->data = NULL;
                 return NULL;
         }
     }
-    free(fp);
     /* direntry is *.[ch] regular file */
-    files = llist_add_to(files, afp);
+    f = xmalloc(sizeof(file_list_t));
+    f->name = afp;
+    f->ext = strrchr(afp, '.') + 1;
+    f->size = st.st_size;
+    files = llist_add_to(files, (char *)f);
     return NULL;
 }
 
@@ -679,6 +686,7 @@ static void scan_dir_find_ch_files(char *p)
     llist_t *d;
     struct dirent *de;
     DIR *dir;
+    size_t dirlen;
 
     dirs = llist_add_to(NULL, p);
     /* emulate recursive */
@@ -688,10 +696,12 @@ static void scan_dir_find_ch_files(char *p)
             dir = opendir(dirs->data);
             if (dir == NULL)
                 fprintf(stderr, "Warning: opendir(%s): %m", dirs->data);
+            dirlen = strlen(dirs->data);
             while ((de = readdir(dir)) != NULL) {
-                d = filter_chd(de->d_name, dirs->data, d_add);
-                if(d)
-                    d_add = d;
+                char *found_dir = filter_chd(de->d_name, dirs->data, dirlen);
+
+                if(found_dir)
+                    d_add = llist_add_to(d_add, found_dir);
             }
             closedir(dir);
             if(dirs->data != p)
@@ -702,15 +712,10 @@ static void scan_dir_find_ch_files(char *p)
         }
         dirs = d_add;
     }
-    for(d = configs; d; d = d->link) {
-        if(d->data) {
-            /* configs.h placed outsize of "." */
-            c_lex(d->data, 1);
-            free(d->data);
-        }
-    }
 }
 
+static char *pwd;
+
 int main(int argc, char **argv)
 {
         int generate_dep = 1;
@@ -718,6 +723,22 @@ int main(int argc, char **argv)
         int i;
         llist_t *fl;
 
+        {
+            /* for bb_simplify_path */
+            /* libbb xgetcwd(), this program have not chdir() */
+            unsigned path_max = 512;
+
+            s = xmalloc (path_max);
+#define PATH_INCR 32
+            while (getcwd (s, path_max) == NULL) {
+                if(errno != ERANGE)
+                    bb_error_d("getcwd: %m");
+                path_max += PATH_INCR;
+                s = xrealloc (s, path_max);
+                }
+            pwd = s;
+        }
+
         while ((i = getopt(argc, argv, "I:c:dk:w")) > 0) {
                 switch(i) {
                     case 'I':
@@ -742,9 +763,6 @@ int main(int argc, char **argv)
                             show_usage();
                 }
         }
-        if(argc > optind)
-            show_usage();
-
         /* defaults */
         if(kp == NULL)
             kp = bb_simplify_path(INCLUDE_CONFIG_PATH);
@@ -754,13 +772,57 @@ int main(int argc, char **argv)
             s = bb_simplify_path(INCLUDE_CONFIG_KEYS_PATH);
             configs = llist_add_to(configs, s);
         }
+        /* globals initialize */
+        /* for c_lex */
+        pagesizem1 = getpagesize() - 1;
+        id_s = xmalloc(mema_id);
+        for(i = 0; i < 256; i++) {
+            /* set unparsed chars for speed up of parser */
+            if(!ISALNUM(i) && i != CHR && i != STR &&
+                              i != POUND && i != REM && i != BS)
+                first_chars[i] = ANY;
+        }
+        first_chars[i] = '-';   /* L_EOF */
+
+        kp_len = strlen(kp);
+        if(stat(kp, &st_kp))
+            bb_error_d("stat(%s): %m", kp);
+        if(!S_ISDIR(st_kp.st_mode))
+            bb_error_d("%s is not directory", kp);
+
+        /* main loops */
+        argv += optind;
+        if(*argv) {
+            while(*argv)
+                scan_dir_find_ch_files(*argv++);
+        } else {
+                scan_dir_find_ch_files(".");
+        }
+
+        for(fl = configs; fl; fl = fl->link) {
+            if(fl->data) {
+                /* configs.h placed outsize of scanned dirs or not "*.ch" */
+                struct stat st;
+
+                if(stat(fl->data, &st))
+                    bb_error_d("stat(%s): %m", fl->data);
+                c_lex(fl->data, st.st_size);
+                free(fl->data);
+            }
+        }
+        free(configs);
+        configs = NULL;     /* flag read config --> parse sourses mode */
 
-        scan_dir_find_ch_files(".");
         for(fl = files; fl; fl = fl->link) {
-                c_lex(fl->data, 0);
+                file_list_t *t = (file_list_t *)(fl->data);
+                c_lex(t->name, t->size);
                 if(generate_dep) {
-                        i = show_dep(1, Ifound, fl->data);
-                        i = show_dep(i, key_top, fl->data);
+                        if(t->ext[0] == 'c') {
+                            /* *.c -> *.o */
+                            t->ext[0] = 'o';
+                        }
+                        i = show_dep(1, Ifound, t->name);
+                        i = show_dep(i, key_top, t->name);
                         if(i == 0)
                                 putchar('\n');
                 }
@@ -768,6 +830,7 @@ int main(int argc, char **argv)
         return 0;
 }
 
+/* partial and simplify libbb routine */
 static void bb_error_d(const char *s, ...)
 {
         va_list p;
@@ -836,24 +899,10 @@ static char *bb_simplify_path(const char *path)
         char *s, *start, *p;
 
         if (path[0] == '/')
-              start = bb_xstrdup(path);
+                start = bb_xstrdup(path);
         else {
-              static char *pwd;
-
-              if(pwd == NULL) {
-                    /* is not libbb, but this program have not chdir() */
-                    unsigned path_max = 512;
-                    char *cwd = xmalloc (path_max);
-#define PATH_INCR 32
-                    while (getcwd (cwd, path_max) == NULL) {
-                        if(errno != ERANGE)
-                            bb_error_d("getcwd: %m");
-                        path_max += PATH_INCR;
-                        cwd = xrealloc (cwd, path_max);
-                    }
-                    pwd = cwd;
-            }
-            start = bb_asprint("%s/%s", pwd, path);
+                /* is not libbb, but this program have not chdir() */
+                start = bb_asprint("%s/%s", pwd, path);
         }
         p = s = start;