preparatory cleanup patch for tab completion fixes

renames and deinlines a few functions

function                                             old     new   delta
input_tab                                              -    1041   +1041
complete_cmd_dir_file                                  -     699    +699
complete_username                                      -     121    +121
username_completion                                  121       -    -121
read_line_input                                     5002    3313   -1689
------------------------------------------------------------------------------
(add/remove: 3/1 grow/shrink: 0/1 up/down: 1861/-1810)         Total: 51 bytes

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

1 files changed, 65 insertions, 61 deletions

diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 35f1d0031..7bb709f9d 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -1,6 +1,6 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Termios command line History and Editing.
+ * Command line editing.
  *
  * Copyright (c) 1986-2003 may safely be consumed by a BSD or GPL license.
  * Written by:   Vladimir Oleynik <dzo@simtreas.ru>
@@ -194,7 +194,7 @@ static void deinit_S(void)
 {
 #if ENABLE_FEATURE_EDITING_FANCY_PROMPT
         /* This one is allocated only if FANCY_PROMPT is on
-         * (otherwise it points to verbatim prompt (NOT malloced) */
+         * (otherwise it points to verbatim prompt (NOT malloced)) */
         free((char*)cmdedit_prompt);
 #endif
 #if ENABLE_USERNAME_OR_HOMEDIR
@@ -213,7 +213,7 @@ static size_t load_string(const char *src, int maxsize)
         ssize_t len = mbstowcs(command_ps, src, maxsize - 1);
         if (len < 0)
                 len = 0;
-        command_ps[len] = 0;
+        command_ps[len] = BB_NUL;
         return len;
 }
 static unsigned save_string(char *dst, unsigned maxsize)
@@ -234,17 +234,17 @@ static unsigned save_string(char *dst, unsigned maxsize)
                 int n = srcpos;
 
                 /* Convert up to 1st invalid byte (or up to end) */
-                while ((wc = command_ps[srcpos]) != 0
+                while ((wc = command_ps[srcpos]) != BB_NUL
                     && !unicode_is_raw_byte(wc)
                 ) {
                         srcpos++;
                 }
-                command_ps[srcpos] = 0;
+                command_ps[srcpos] = BB_NUL;
                 n = wcstombs(dst + dstpos, command_ps + n, maxsize - dstpos);
                 if (n < 0) /* should not happen */
                         break;
                 dstpos += n;
-                if (wc == 0) /* usually is */
+                if (wc == BB_NUL) /* usually is */
                         break;
 
                 /* We do have invalid byte here! */
@@ -639,7 +639,7 @@ static char *username_path_completion(char *ud)
 }
 
 /* ~use<tab> - find all users with this prefix */
-static NOINLINE void username_completion(const char *ud)
+static NOINLINE void complete_username(const char *ud)
 {
         /* Using _r function to avoid pulling in static buffers */
         char line_buff[256];
@@ -659,7 +659,7 @@ static NOINLINE void username_completion(const char *ud)
         }
         endpwent();
 }
-#endif  /* FEATURE_COMMAND_USERNAME_COMPLETION */
+#endif  /* FEATURE_USERNAME_COMPLETION */
 
 enum {
         FIND_EXE_ONLY = 0,
@@ -710,7 +710,7 @@ static int path_parse(char ***p)
         return npth;
 }
 
-static void exe_n_cwd_tab_completion(char *command, int type)
+static NOINLINE void complete_cmd_dir_file(char *command, int type)
 {
         char *path1[1];
         char **paths = path1;
@@ -799,24 +799,25 @@ static void exe_n_cwd_tab_completion(char *command, int type)
         free(dirbuf);
 }
 
+/* build_match_prefix:
+ * On entry, matchBuf contains everything up to cursor at the moment <tab>
+ * was pressed. This function looks at it, figures out what part of it
+ * constitutes the command/file/directory prefix to use for completion,
+ * and rewrites matchBuf to contain only that part.
+ */
+/* Helpers: */
 /* QUOT is used on elements of int_buf[], which are bytes,
  * not Unicode chars. Therefore it works correctly even in Unicode mode.
  */
 #define QUOT (UCHAR_MAX+1)
-
 #define int_buf (S.find_match__int_buf)
 #define pos_buf (S.find_match__pos_buf)
-/* is must be <= in */
-static void collapse_pos(int is, int in)
+static void collapse_pos(int beg, int end)
 {
-        memmove(int_buf+is, int_buf+in, (MAX_LINELEN+1-in) * sizeof(int_buf[0]));
-        memmove(pos_buf+is, pos_buf+in, (MAX_LINELEN+1-in) * sizeof(pos_buf[0]));
+        /* beg must be <= end */
+        memmove(int_buf+beg, int_buf+end, (MAX_LINELEN+1-end) * sizeof(int_buf[0]));
+        memmove(pos_buf+beg, pos_buf+end, (MAX_LINELEN+1-end) * sizeof(pos_buf[0]));
 }
-/* On entry, matchBuf contains everything up to cursor at the moment <tab>
- * was pressed. This function looks at it, figures out what part of it
- * constitutes the command/file/directory prefix to use for completion,
- * and rewrites matchBuf to contain only that part.
- */
 static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
 {
         int i, j;
@@ -826,17 +827,16 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
 /*      int16_t int_buf[MAX_LINELEN + 1]; */
 /*      int16_t pos_buf[MAX_LINELEN + 1]; */
 
-        /* set to integer dimension characters and own positions */
         for (i = 0;; i++) {
                 int_buf[i] = (unsigned char)matchBuf[i];
                 if (int_buf[i] == 0) {
-                        pos_buf[i] = -1; /* end-fo-line indicator */
+                        pos_buf[i] = -1; /* end-of-line indicator */
                         break;
                 }
                 pos_buf[i] = i;
         }
 
-        /* mask \+symbol and convert '\t' to ' ' */
+        /* Mark every \c as "quoted c" */
         for (i = j = 0; matchBuf[i]; i++, j++) {
                 if (matchBuf[i] == '\\') {
                         collapse_pos(j, j + 1);
@@ -844,7 +844,7 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         i++;
                 }
         }
-        /* mask "symbols" or 'symbols' */
+        /* Quote-mark "chars" and 'chars' */
         c2 = 0;
         for (i = 0; int_buf[i]; i++) {
                 c = int_buf[i];
@@ -861,8 +861,10 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         int_buf[i] |= QUOT;
         }
 
-        /* skip commands with arguments if line has commands delimiters */
-        /* ';' ';;' '&' '|' '&&' '||' but '>&' '<&' '>|' */
+        /* Remove everything up to command delimiters:
+         * ';' ';;' '&' '|' '&&' '||',
+         * but careful with '>&' '<&' '>|'
+         */
         for (i = 0; int_buf[i]; i++) {
                 int n;
                 c = int_buf[i];
@@ -879,28 +881,29 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                 }
                 if (n) {
                         collapse_pos(0, i + n);
-                        i = -1;  /* hack incremet */
+                        i = -1;  /* hack increment */
                 }
         }
-        /* collapse `command...` */
+        /* Remove all `cmd` */
         for (i = 0; int_buf[i]; i++) {
                 if (int_buf[i] == '`') {
-                        for (j = i + 1; int_buf[j]; j++)
+                        for (j = i + 1; int_buf[j]; j++) {
                                 if (int_buf[j] == '`') {
                                         collapse_pos(i, j + 1);
                                         j = 0;
                                         break;
                                 }
+                        }
                         if (j) {
-                                /* not found closing ` - command mode, collapse all previous */
+                                /* No closing ` - command mode, remove all up to ` */
                                 collapse_pos(0, i + 1);
                                 break;
-                        } else
-                                i--;  /* hack incremet */
+                        }
+                        i--;  /* hack increment */
                 }
         }
 
-        /* collapse (command...(command...)...) or {command...{command...}...} */
+        /* Remove (command...(command...)...) and {command...{command...}...} */
         c = 0;  /* "recursive" level */
         c2 = 0;
         for (i = 0; int_buf[i]; i++) {
@@ -910,7 +913,7 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         else
                                 c2++;
                         collapse_pos(0, i + 1);
-                        i = -1;  /* hack incremet */
+                        i = -1;  /* hack increment */
                 }
         }
         for (i = 0; pos_buf[i] >= 0 && (c > 0 || c2 > 0); i++) {
@@ -920,22 +923,23 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         else
                                 c2--;
                         collapse_pos(0, i + 1);
-                        i = -1;  /* hack incremet */
+                        i = -1;  /* hack increment */
                 }
         }
 
-        /* skip first not quote space */
+        /* Remove leading unquoted spaces */
         for (i = 0; int_buf[i]; i++)
                 if (int_buf[i] != ' ')
                         break;
         if (i)
                 collapse_pos(0, i);
 
-        /* set find mode for completion */
+        /* Determine completion mode */
         command_mode = FIND_EXE_ONLY;
         for (i = 0; int_buf[i]; i++) {
                 if (int_buf[i] == ' ' || int_buf[i] == '<' || int_buf[i] == '>') {
-                        if (int_buf[i] == ' ' && command_mode == FIND_EXE_ONLY
+                        if (int_buf[i] == ' '
+                         && command_mode == FIND_EXE_ONLY
                          && matchBuf[pos_buf[0]] == 'c'
                          && matchBuf[pos_buf[1]] == 'd'
                         ) {
@@ -946,9 +950,10 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         }
                 }
         }
+
+        /* Remove everything except last word */
         for (i = 0; int_buf[i]; i++) /* quasi-strlen(int_buf) */
                 continue;
-        /* find last word */
         for (--i; i >= 0; i--) {
                 c = int_buf[i];
                 if (c == ' ' || c == '<' || c == '>' || c == '|' || c == '&') {
@@ -956,7 +961,7 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
                         break;
                 }
         }
-        /* skip first not quoted '\'' or '"' */
+        /* Skip all leading unquoted ' or " */
         for (i = 0; int_buf[i] == '\'' || int_buf[i] == '"'; i++)
                 continue;
         /* collapse quote or unquote // or /~ */
@@ -982,8 +987,8 @@ static NOINLINE int build_match_prefix(char *matchBuf, int *len_with_quotes)
 #undef pos_buf
 
 /*
- * display by column (original idea from ls applet,
- * very optimized by me :)
+ * Display by column (original idea from ls applet,
+ * very optimized by me [Vladimir] :)
  */
 static void showfiles(void)
 {
@@ -1040,7 +1045,7 @@ static char *add_quote_for_spec_chars(char *found)
 }
 
 /* Do TAB completion */
-static void input_tab(smallint *lastWasTab)
+static NOINLINE void input_tab(smallint *lastWasTab)
 {
         if (!(state->flags & TAB_COMPLETION))
                 return;
@@ -1057,7 +1062,7 @@ static void input_tab(smallint *lastWasTab)
                 int cursor_mb;
 #endif
 
-                *lastWasTab = TRUE;             /* flop trigger */
+                *lastWasTab = 1;
 
                 /* Make a local copy of the string --
                  * up to the position of the cursor */
@@ -1066,7 +1071,7 @@ static void input_tab(smallint *lastWasTab)
 #else
                 {
                         CHAR_T wc = command_ps[cursor];
-                        command_ps[cursor] = 0;
+                        command_ps[cursor] = BB_NUL;
                         save_string(matchBuf, MAX_LINELEN);
                         command_ps[cursor] = wc;
                         cursor_mb = strlen(matchBuf);
@@ -1084,26 +1089,25 @@ static void input_tab(smallint *lastWasTab)
                  * then try completing this word as a username. */
                 if (state->flags & USERNAME_COMPLETION)
                         if (matchBuf[0] == '~' && strchr(matchBuf, '/') == NULL)
-                                username_completion(matchBuf);
+                                complete_username(matchBuf);
 #endif
-                /* Try to match any executable in our path and everything
-                 * in the current working directory */
+                /* Try to match a command in $PATH, or a directory, or a file */
                 if (!matches)
-                        exe_n_cwd_tab_completion(matchBuf, find_type);
-                /* Sort, then remove any duplicates found */
+                        complete_cmd_dir_file(matchBuf, find_type);
+                /* Remove duplicates */
                 if (matches) {
                         unsigned i;
                         unsigned n = 0;
                         qsort_string_vector(matches, num_matches);
                         for (i = 0; i < num_matches - 1; ++i) {
-                                if (matches[i] && matches[i+1]) { /* paranoia */
+                                //if (matches[i] && matches[i+1]) { /* paranoia */
                                         if (strcmp(matches[i], matches[i+1]) == 0) {
                                                 free(matches[i]);
-                                                matches[i] = NULL; /* paranoia */
+                                                //matches[i] = NULL; /* paranoia */
                                         } else {
                                                 matches[n++] = matches[i];
                                         }
-                                }
+                                //}
                         }
                         matches[n++] = matches[i];
                         num_matches = n;
@@ -1113,7 +1117,7 @@ static void input_tab(smallint *lastWasTab)
                         beep();
                         if (!matches)
                                 return; /* no matches at all */
-                        /* find minimal match */
+                        /* Find common prefix */
                         tmp1 = xstrdup(matches[0]);
                         for (tmp = tmp1; *tmp; tmp++) {
                                 for (len_found = 1; len_found < num_matches; len_found++) {
@@ -1123,7 +1127,7 @@ static void input_tab(smallint *lastWasTab)
                                         }
                                 }
                         }
-                        if (*tmp1 == '\0') { /* have unique pfx? */
+                        if (*tmp1 == '\0') { /* have unique prefix? */
                                 free(tmp1); /* no */
                                 return;
                         }
@@ -1131,10 +1135,10 @@ static void input_tab(smallint *lastWasTab)
                         free(tmp1);
                         len_found = strlen(tmp);
                 } else {                        /* exactly one match */
-                        tmp = add_quote_for_spec_chars(matches[0]);
-                        /* for next completion current found */
-                        *lastWasTab = FALSE;
+                        /* Next <tab> is not a double-tab */
+                        *lastWasTab = 0;
 
+                        tmp = add_quote_for_spec_chars(matches[0]);
                         len_found = strlen(tmp);
                         if (tmp[len_found-1] != '/') {
                                 tmp[len_found] = ' ';
@@ -1199,7 +1203,7 @@ static void input_tab(smallint *lastWasTab)
         }
 }
 
-#endif  /* FEATURE_COMMAND_TAB_COMPLETION */
+#endif  /* FEATURE_TAB_COMPLETION */
 
 
 line_input_t* FAST_FUNC new_line_input_t(int flags)
@@ -1899,7 +1903,7 @@ int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, li
 {
         int len;
 #if ENABLE_FEATURE_TAB_COMPLETION
-        smallint lastWasTab = FALSE;
+        smallint lastWasTab = 0;
 #endif
         smallint break_out = 0;
 #if ENABLE_FEATURE_EDITING_VI
@@ -2375,7 +2379,7 @@ int FAST_FUNC read_line_input(const char *prompt, char *command, int maxsize, li
 
 #if ENABLE_FEATURE_TAB_COMPLETION
                 if (ic_raw != '\t')
-                        lastWasTab = FALSE;
+                        lastWasTab = 0;
 #endif
         } /* while (1) */
 
@@ -2469,7 +2473,7 @@ int main(int argc, char **argv)
                 l = read_line_input(prompt, buff);
                 if (l <= 0 || buff[l-1] != '\n')
                         break;
-                buff[l-1] = 0;
+                buff[l-1] = '\0';
                 printf("*** read_line_input() returned line =%s=\n", buff);
         }
         printf("*** read_line_input() detect ^D\n");