76939e7b7
Denys Vlasenko
2010-09-03
Subject
lineedit: allocate matchBuf only temporarily: saves MAX_LINELEN bytes
Binary
No binary (build failed)
Architecture & Compiler Flags
—
Build Log
(log yok)
Commit Diff GitHub →
libbb/lineedit.c+48 -45
| @@ -150,11 +150,6 @@ struct lineedit_statics { | |
| #if ENABLE_FEATURE_EDITING_ASK_TERMINAL | |
| smallint sent_ESC_br6n; | |
| #endif | |
| - | |
| - | /* Formerly these were big buffers on stack: */ |
| - | #if ENABLE_FEATURE_TAB_COMPLETION |
| - | char input_tab__matchBuf[MAX_LINELEN]; |
| - | #endif |
| }; | |
| /* See lineedit_ptr_hack.c */ | |
| @@ -810,17 +805,17 @@ static NOINLINE unsigned complete_cmd_dir_file(const char *command, int type) | |
| } | |
| /* build_match_prefix: | |
| - | * On entry, matchBuf contains everything up to cursor at the moment <tab> |
| + | * On entry, match_buf 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. |
| + | * and rewrites match_buf to contain only that part. |
| */ | |
| + | #define dbg_bmp 0 |
| /* 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 dbg_bmp 0 |
| static void remove_chunk(int16_t *int_buf, int beg, int end) | |
| { | |
| /* beg must be <= end */ | |
| @@ -837,25 +832,29 @@ static void remove_chunk(int16_t *int_buf, int beg, int end) | |
| bb_putchar('\n'); | |
| } | |
| } | |
| - | static NOINLINE int build_match_prefix(char *matchBuf) |
| + | /* Caller ensures that match_buf points to a malloced buffer |
| + | * big enough to hold strlen(match_buf)*2 + 2 |
| + | */ |
| + | static NOINLINE int build_match_prefix(char *match_buf) |
| { | |
| int i, j; | |
| int command_mode; | |
| - | int16_t *int_buf; |
| + | int16_t *int_buf = (int16_t*)match_buf; |
| - | if (dbg_bmp) printf("\n%s\n", matchBuf); |
| + | if (dbg_bmp) printf("\n%s\n", match_buf); |
| - | int_buf = xmalloc(sizeof(int_buf[0]) * (strlen(matchBuf) + 1)); |
| - | i = 0; |
| - | while ((int_buf[i] = (unsigned char)matchBuf[i]) != '\0') |
| - | i++; |
| + | /* Copy in reverse order, since they overlap */ |
| + | i = strlen(match_buf); |
| + | do { |
| + | int_buf[i] = (unsigned char)match_buf[i]; |
| + | i--; |
| + | } while (i >= 0); |
| /* Mark every \c as "quoted c" */ | |
| - | for (i = j = 0; matchBuf[i]; i++, j++) { |
| - | if (matchBuf[i] == '\\') { |
| - | remove_chunk(int_buf, j, j + 1); |
| - | int_buf[j] |= QUOT; |
| - | i++; |
| + | for (i = 0; int_buf[i]; i++) { |
| + | if (int_buf[i] == '\\') { |
| + | remove_chunk(int_buf, i, i + 1); |
| + | int_buf[i] |= QUOT; |
| } | |
| } | |
| /* Quote-mark "chars" and 'chars', drop delimiters */ | |
| @@ -964,13 +963,12 @@ static NOINLINE int build_match_prefix(char *matchBuf) | |
| } | |
| } | |
| - | /* Store only match prefix */ |
| + | /* Convert back to string of _chars_ */ |
| i = 0; | |
| - | while ((matchBuf[i] = int_buf[i]) != '\0') |
| + | while ((match_buf[i] = int_buf[i]) != '\0') |
| i++; | |
| - | free(int_buf); |
| - | if (dbg_bmp) printf("final matchBuf:'%s'\n", matchBuf); |
| + | if (dbg_bmp) printf("final match_buf:'%s'\n", match_buf); |
| return command_mode; | |
| } | |
| @@ -1037,9 +1035,8 @@ static char *add_quote_for_spec_chars(char *found) | |
| static NOINLINE void input_tab(smallint *lastWasTab) | |
| { | |
| char *chosen_match; | |
| + | char *match_buf; |
| size_t len_found; | |
| - | /* char matchBuf[MAX_LINELEN]; */ |
| - | #define matchBuf (S.input_tab__matchBuf) |
| /* Length of string used for matching */ | |
| unsigned match_pfx_len = match_pfx_len; | |
| int find_type; | |
| @@ -1065,21 +1062,26 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| } | |
| *lastWasTab = 1; | |
| + | chosen_match = NULL; |
| - | /* Make a local copy of the string -- |
| - | * up to the position of the cursor */ |
| + | /* Make a local copy of the string up to the position of the cursor. |
| + | * build_match_prefix will expand it into int16_t's, need to allocate |
| + | * twice as much as the string_len+1. |
| + | * (we then also (ab)use this extra space later - see (**)) |
| + | */ |
| + | match_buf = xmalloc(MAX_LINELEN * sizeof(int16_t)); |
| #if !ENABLE_UNICODE_SUPPORT | |
| - | save_string(matchBuf, cursor + 1); |
| + | save_string(match_buf, cursor + 1); /* +1 for NUL */ |
| #else | |
| { | |
| CHAR_T wc = command_ps[cursor]; | |
| command_ps[cursor] = BB_NUL; | |
| - | save_string(matchBuf, MAX_LINELEN); |
| + | save_string(match_buf, MAX_LINELEN); |
| command_ps[cursor] = wc; | |
| - | cursor_mb = strlen(matchBuf); |
| + | cursor_mb = strlen(match_buf); |
| } | |
| #endif | |
| - | find_type = build_match_prefix(matchBuf); |
| + | find_type = build_match_prefix(match_buf); |
| /* Free up any memory already allocated */ | |
| free_tab_completion_data(); | |
| @@ -1088,12 +1090,12 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| /* If the word starts with `~' and there is no slash in the word, | |
| * then try completing this word as a username. */ | |
| if (state->flags & USERNAME_COMPLETION) | |
| - | if (matchBuf[0] == '~' && strchr(matchBuf, '/') == NULL) |
| - | match_pfx_len = complete_username(matchBuf); |
| + | if (match_buf[0] == '~' && strchr(match_buf, '/') == NULL) |
| + | match_pfx_len = complete_username(match_buf); |
| #endif | |
| /* Try to match a command in $PATH, or a directory, or a file */ | |
| if (!matches) | |
| - | match_pfx_len = complete_cmd_dir_file(matchBuf, find_type); |
| + | match_pfx_len = complete_cmd_dir_file(match_buf, find_type); |
| /* Remove duplicates */ | |
| if (matches) { | |
| unsigned i; | |
| @@ -1117,7 +1119,7 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| char *cp; | |
| beep(); | |
| if (!matches) | |
| - | return; /* no matches at all */ |
| + | goto ret; /* no matches at all */ |
| /* Find common prefix */ | |
| chosen_match = xstrdup(matches[0]); | |
| for (cp = chosen_match; *cp; cp++) { | |
| @@ -1130,8 +1132,7 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| } | |
| stop: | |
| if (cp == chosen_match) { /* have unique prefix? */ | |
| - | free(chosen_match); /* no */ |
| - | return; |
| + | goto ret; /* no */ |
| } | |
| *cp = '\0'; | |
| cp = add_quote_for_spec_chars(chosen_match); | |
| @@ -1158,9 +1159,9 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| if ((int)(len_found - match_pfx_len + command_len) < S.maxsize) { | |
| int pos; | |
| /* save tail */ | |
| - | strcpy(matchBuf, &command_ps[cursor]); |
| + | strcpy(match_buf, &command_ps[cursor]); |
| /* add match and tail */ | |
| - | sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, matchBuf); |
| + | sprintf(&command_ps[cursor], "%s%s", chosen_match + match_pfx_len, match_buf); |
| command_len = strlen(command_ps); | |
| /* new pos */ | |
| pos = cursor + len_found - match_pfx_len; | |
| @@ -1169,19 +1170,20 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| } | |
| #else | |
| { | |
| - | char command[MAX_LINELEN]; |
| - | int len = save_string(command, sizeof(command)); |
| + | /* Use 2nd half of match_buf as scratch space - see (**) */ |
| + | char *command = match_buf + MAX_LINELEN; |
| + | int len = save_string(command, MAX_LINELEN); |
| /* Have space to place the match? */ | |
| /* cursor_mb + (len_found - match_pfx_len) + (len - cursor_mb) */ | |
| if ((int)(len_found - match_pfx_len + len) < MAX_LINELEN) { | |
| int pos; | |
| /* save tail */ | |
| - | strcpy(matchBuf, &command[cursor_mb]); |
| + | strcpy(match_buf, &command[cursor_mb]); |
| /* where do we want to have cursor after all? */ | |
| strcpy(&command[cursor_mb], chosen_match + match_pfx_len); | |
| len = load_string(command, S.maxsize); | |
| /* add match and tail */ | |
| - | sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, matchBuf); |
| + | sprintf(&command[cursor_mb], "%s%s", chosen_match + match_pfx_len, match_buf); |
| command_len = load_string(command, S.maxsize); | |
| /* write out the matched command */ | |
| /* paranoia: load_string can return 0 on conv error, | |
| @@ -1191,8 +1193,9 @@ static NOINLINE void input_tab(smallint *lastWasTab) | |
| } | |
| } | |
| #endif | |
| + | ret: |
| free(chosen_match); | |
| - | #undef matchBuf |
| + | free(match_buf); |
| } | |
| #endif /* FEATURE_TAB_COMPLETION */ | |