lineedit: stop using both data/bss and tons of stack.
stack usage was ~10 kb!
unfortunately, noticeable code size growth:
text data bss dec hex filename
9252 12 181 9445 24e5 busybox.t7/libbb/lineedit.o
9714 4 0 9718 25f6 busybox.t8/libbb/lineedit.o
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index f65e852..4d33834 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -41,7 +41,6 @@
#define ENABLE_FEATURE_TAB_COMPLETION 0
#define ENABLE_FEATURE_USERNAME_COMPLETION 0
#define ENABLE_FEATURE_NONPRINTABLE_INVERSE_PUT 0
-#define ENABLE_FEATURE_CLEAN_UP 0
#endif /* TEST */
@@ -56,36 +55,118 @@
#endif
#define ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR \
-(ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
+ (ENABLE_FEATURE_USERNAME_COMPLETION || ENABLE_FEATURE_EDITING_FANCY_PROMPT)
+#define USE_FEATURE_GETUSERNAME_AND_HOMEDIR(...)
+#if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
+#undef USE_FEATURE_GETUSERNAME_AND_HOMEDIR
+#define USE_FEATURE_GETUSERNAME_AND_HOMEDIR(...) __VA_ARGS__
+#endif
-enum { MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN };
+enum {
+ /* We use int16_t for positions, need to limit line len */
+ MAX_LINELEN = CONFIG_FEATURE_EDITING_MAX_LEN < 0x7ff0
+ ? CONFIG_FEATURE_EDITING_MAX_LEN
+ : 0x7ff0
+};
-static line_input_t *state;
+#if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
+static const char null_str[] ALIGN1 = "";
+#endif
-static struct termios initial_settings, new_settings;
+/* We try to minimize both static and stack usage. */
+struct statics {
+ line_input_t *state;
-static volatile unsigned cmdedit_termw = 80; /* actual terminal width */
+ volatile unsigned cmdedit_termw; /* = 80; */ /* actual terminal width */
+ sighandler_t previous_SIGWINCH_handler;
-static int cmdedit_x; /* real x terminal position */
-static int cmdedit_y; /* pseudoreal y terminal position */
-static int cmdedit_prmt_len; /* length of prompt (without colors etc) */
-static unsigned cursor;
-static unsigned command_len;
-static char *command_ps;
-static const char *cmdedit_prompt;
+ int cmdedit_x; /* real x terminal position */
+ int cmdedit_y; /* pseudoreal y terminal position */
+ int cmdedit_prmt_len; /* length of prompt (without colors etc) */
+ unsigned cursor;
+ unsigned command_len;
+ char *command_ps;
+
+ const char *cmdedit_prompt;
#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
-static char *hostname_buf;
-static int num_ok_lines = 1;
+ char *hostname_buf;
+ int num_ok_lines; /* = 1; */
#endif
#if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
-static const char null_str[] = "";
-static char *user_buf;
-static char *home_pwd_buf = (char*)null_str;
+ char *user_buf;
+ char *home_pwd_buf; /* = (char*)null_str; */
#endif
+#if ENABLE_FEATURE_TAB_COMPLETION
+ char **matches;
+ unsigned num_matches;
+#endif
+
+#if ENABLE_FEATURE_EDITING_VI
+#define DELBUFSIZ 128
+ char *delptr;
+ smallint newdelflag; /* whether delbuf should be reused yet */
+ char delbuf[DELBUFSIZ]; /* a place to store deleted characters */
+#endif
+
+ /* Formerly these were big buffers on stack: */
+#if ENABLE_FEATURE_TAB_COMPLETION
+ char exe_n_cwd_tab_completion__dirbuf[MAX_LINELEN];
+ char input_tab__matchBuf[MAX_LINELEN];
+ int16_t find_match__int_buf[MAX_LINELEN + 1]; /* need to have 9 bits at least */
+ int16_t find_match__pos_buf[MAX_LINELEN + 1];
+#endif
+};
+
+static struct statics *const ptr_to_statics __attribute__ ((section (".data")));
+
+#define S (*ptr_to_statics)
+#define state (S.state )
+#define cmdedit_termw (S.cmdedit_termw )
+#define previous_SIGWINCH_handler (S.previous_SIGWINCH_handler)
+#define cmdedit_x (S.cmdedit_x )
+#define cmdedit_y (S.cmdedit_y )
+#define cmdedit_prmt_len (S.cmdedit_prmt_len)
+#define cursor (S.cursor )
+#define command_len (S.command_len )
+#define command_ps (S.command_ps )
+#define cmdedit_prompt (S.cmdedit_prompt )
+#define hostname_buf (S.hostname_buf )
+#define num_ok_lines (S.num_ok_lines )
+#define user_buf (S.user_buf )
+#define home_pwd_buf (S.home_pwd_buf )
+#define matches (S.matches )
+#define num_matches (S.num_matches )
+#define delptr (S.delptr )
+#define newdelflag (S.newdelflag )
+#define delbuf (S.delbuf )
+
+#define INIT_S() do { \
+ (*(struct statics**)&ptr_to_statics) = xzalloc(sizeof(S)); \
+ cmdedit_termw = 80; \
+ USE_FEATURE_EDITING_FANCY_PROMPT(num_ok_lines = 1;) \
+ USE_FEATURE_GETUSERNAME_AND_HOMEDIR(home_pwd_buf = (char*)null_str;) \
+} while (0)
+static void deinit_S(void)
+{
+#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
+ free(hostname_buf);
+ /* This one is allocated only if FANCY_PROMPT is on
+ * (otherwise it points to verbatim prompt (NOT malloced) */
+ free((char*)cmdedit_prompt);
+#endif
+#if ENABLE_FEATURE_GETUSERNAME_AND_HOMEDIR
+ free(user_buf);
+ if (home_pwd_buf != null_str)
+ free(home_pwd_buf);
+#endif
+ free(ptr_to_statics);
+}
+#define DEINIT_S() deinit_S()
+
/* Put 'command_ps[cursor]', cursor++.
* Advance cursor on screen. If we reached right margin, scroll text up
* and remove terminal margin effect by printing 'next_char' */
@@ -110,8 +191,7 @@
} else
#endif
{
- if (initial_settings.c_lflag & ECHO)
- bb_putchar(c);
+ bb_putchar(c);
}
if (++cmdedit_x >= cmdedit_termw) {
/* terminal is scrolled down */
@@ -204,13 +284,6 @@
input_backward(back_cursor);
}
-#if ENABLE_FEATURE_EDITING_VI
-#define DELBUFSIZ 128
-static char *delbuf; /* a (malloced) place to store deleted characters */
-static char *delp;
-static char newdelflag; /* whether delbuf should be reused yet */
-#endif
-
/* Delete the char in front of the cursor, optionally saving it
* for later putback */
static void input_delete(int save)
@@ -223,14 +296,11 @@
#if ENABLE_FEATURE_EDITING_VI
if (save) {
if (newdelflag) {
- if (!delbuf)
- delbuf = malloc(DELBUFSIZ);
- /* safe if malloc fails */
- delp = delbuf;
+ delptr = delbuf;
newdelflag = 0;
}
- if (delbuf && (delp - delbuf < DELBUFSIZ))
- *delp++ = command_ps[j];
+ if ((delptr - delbuf) < DELBUFSIZ)
+ *delptr++ = command_ps[j];
}
#endif
@@ -245,7 +315,7 @@
static void put(void)
{
int ocursor;
- int j = delp - delbuf;
+ int j = delptr - delbuf;
if (j == 0)
return;
@@ -275,12 +345,8 @@
cmdedit_set_out_char(command_ps[cursor + 1]);
}
-
#if ENABLE_FEATURE_TAB_COMPLETION
-static char **matches;
-static unsigned num_matches;
-
static void free_tab_completion_data(void)
{
if (matches) {
@@ -329,11 +395,8 @@
}
if (home) {
if ((userlen + strlen(home) + 1) < MAX_LINELEN) {
- char temp2[MAX_LINELEN]; /* argument size */
-
/* /home/user/... */
- sprintf(temp2, "%s%s", home, ud);
- strcpy(sav_ud, temp2);
+ sprintf(sav_ud, "%s%s", home, ud);
}
}
} else {
@@ -411,7 +474,6 @@
{
DIR *dir;
struct dirent *next;
- char dirbuf[MAX_LINELEN];
struct stat st;
char *path1[1];
char **paths = path1;
@@ -419,6 +481,8 @@
int i;
char *found;
char *pfind = strrchr(command, '/');
+/* char dirbuf[MAX_LINELEN]; */
+#define dirbuf (S.exe_n_cwd_tab_completion__dirbuf)
npaths = 1;
path1[0] = (char*)".";
@@ -492,21 +556,25 @@
free(paths[0]); /* allocated memory only in first member */
free(paths);
}
+#undef dirbuf
}
#define QUOT (UCHAR_MAX+1)
-#define collapse_pos(is, in) { \
- memmove(int_buf+(is), int_buf+(in), (MAX_LINELEN+1-(is)-(in))*sizeof(int)); \
- memmove(pos_buf+(is), pos_buf+(in), (MAX_LINELEN+1-(is)-(in))*sizeof(int)); }
+#define collapse_pos(is, in) do { \
+ memmove(int_buf+(is), int_buf+(in), (MAX_LINELEN+1-(is)-(in)) * sizeof(pos_buf[0])); \
+ memmove(pos_buf+(is), pos_buf+(in), (MAX_LINELEN+1-(is)-(in)) * sizeof(pos_buf[0])); \
+} while (0)
static int find_match(char *matchBuf, int *len_with_quotes)
{
int i, j;
int command_mode;
int c, c2;
- int int_buf[MAX_LINELEN + 1];
- int pos_buf[MAX_LINELEN + 1];
+/* int16_t int_buf[MAX_LINELEN + 1]; */
+/* int16_t pos_buf[MAX_LINELEN + 1]; */
+#define int_buf (S.find_match__int_buf)
+#define pos_buf (S.find_match__pos_buf)
/* set to integer dimension characters and own positions */
for (i = 0;; i++) {
@@ -622,8 +690,8 @@
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
- && matchBuf[pos_buf[0]]=='c'
- && matchBuf[pos_buf[1]]=='d'
+ && matchBuf[pos_buf[0]] == 'c'
+ && matchBuf[pos_buf[1]] == 'd'
) {
command_mode = FIND_DIR_ONLY;
} else {
@@ -657,11 +725,13 @@
matchBuf[c++] = matchBuf[pos_buf[i]];
j = pos_buf[i] + 1;
}
- matchBuf[c] = 0;
+ matchBuf[c] = '\0';
/* old length matchBuf with quotes symbols */
*len_with_quotes = j ? j - pos_buf[0] : 0;
return command_mode;
+#undef int_buf
+#undef pos_buf
}
/*
@@ -724,7 +794,7 @@
}
/* Do TAB completion */
-static void input_tab(int *lastWasTab)
+static void input_tab(smallint *lastWasTab)
{
if (!(state->flags & TAB_COMPLETION))
return;
@@ -732,7 +802,8 @@
if (!*lastWasTab) {
char *tmp, *tmp1;
int len_found;
- char matchBuf[MAX_LINELEN];
+/* char matchBuf[MAX_LINELEN]; */
+#define matchBuf (S.input_tab__matchBuf)
int find_type;
int recalc_pos;
@@ -782,7 +853,6 @@
if (!matches)
return; /* not found */
/* find minimal match */
- // ash: yet another failure in trying to achieve "we don't die on OOM"
tmp1 = xstrdup(matches[0]);
for (tmp = tmp1; *tmp; tmp++)
for (len_found = 1; len_found < num_matches; len_found++)
@@ -811,7 +881,7 @@
/* have space to placed match? */
if ((len_found - strlen(matchBuf) + command_len) < MAX_LINELEN) {
/* before word for match */
- command_ps[cursor - recalc_pos] = 0;
+ command_ps[cursor - recalc_pos] = '\0';
/* save tail line */
strcpy(matchBuf, command_ps + cursor);
/* add match */
@@ -828,6 +898,7 @@
redraw(cmdedit_y, command_len - recalc_pos);
}
free(tmp);
+#undef matchBuf
} else {
/* Ok -- the last char was a TAB. Since they
* just hit TAB again, print a list of all the
@@ -843,8 +914,6 @@
}
}
-#else
-#define input_tab(a) ((void)0)
#endif /* FEATURE_COMMAND_TAB_COMPLETION */
@@ -1079,14 +1148,14 @@
*/
#if !ENABLE_FEATURE_EDITING_FANCY_PROMPT
-static void parse_prompt(const char *prmt_ptr)
+static void parse_and_put_prompt(const char *prmt_ptr)
{
cmdedit_prompt = prmt_ptr;
cmdedit_prmt_len = strlen(prmt_ptr);
put_prompt();
}
#else
-static void parse_prompt(const char *prmt_ptr)
+static void parse_and_put_prompt(const char *prmt_ptr)
{
int prmt_len = 0;
size_t cur_prmt_len = 0;
@@ -1114,7 +1183,7 @@
c = bb_process_escape_sequence(&prmt_ptr);
if (prmt_ptr == cp) {
- if (*cp == 0)
+ if (*cp == '\0')
break;
c = *prmt_ptr++;
switch (c) {
@@ -1147,7 +1216,7 @@
if (l != 0
&& strncmp(home_pwd_buf, pbuf, l) == 0
&& (pbuf[l]=='/' || pbuf[l]=='\0')
- && strlen(pwd_buf+l)<PATH_MAX
+ && strlen(pwd_buf+l) < PATH_MAX
) {
pbuf = buf2;
*pbuf = '~';
@@ -1188,7 +1257,7 @@
break;
case '[': case ']':
if (c == flg_not_length) {
- flg_not_length = flg_not_length == '[' ? ']' : '[';
+ flg_not_length = (flg_not_length == '[' ? ']' : '[');
continue;
}
break;
@@ -1210,11 +1279,6 @@
}
#endif
-#define setTermSettings(fd, argp) tcsetattr(fd, TCSANOW, argp)
-#define getTermSettings(fd, argp) tcgetattr(fd, argp);
-
-static sighandler_t previous_SIGWINCH_handler;
-
static void cmdedit_setwidth(unsigned w, int redraw_flg)
{
cmdedit_termw = w;
@@ -1261,7 +1325,9 @@
*/
int read_line_input(const char *prompt, char *command, int maxsize, line_input_t *st)
{
- int lastWasTab = FALSE;
+#if ENABLE_FEATURE_TAB_COMPLETION
+ smallint lastWasTab = FALSE;
+#endif
unsigned int ic;
unsigned char c;
smallint break_out = 0;
@@ -1269,14 +1335,22 @@
smallint vi_cmdmode = 0;
smalluint prevc;
#endif
+ struct termios initial_settings;
+ struct termios new_settings;
- getTermSettings(0, (void *) &initial_settings);
- /* Happens when e.g. stty -echo was run before */
- if (!(initial_settings.c_lflag & ECHO)) {
- parse_prompt(prompt);
+ INIT_S();
+
+ if (tcgetattr(STDIN_FILENO, &initial_settings) < 0
+ || !(initial_settings.c_lflag & ECHO)
+ ) {
+ /* Happens when e.g. stty -echo was run before */
+ int len;
+ parse_and_put_prompt(prompt);
fflush(stdout);
fgets(command, maxsize, stdin);
- return strlen(command);
+ len = strlen(command);
+ DEINIT_S();
+ return len;
}
// FIXME: audit & improve this
@@ -1296,7 +1370,7 @@
command_ps = command;
command[0] = '\0';
- memcpy(&new_settings, &initial_settings, sizeof(new_settings));
+ new_settings = initial_settings;
new_settings.c_lflag &= ~ICANON; /* unbuffered input */
/* Turn off echoing and CTRL-C, so we can trap it */
new_settings.c_lflag &= ~(ECHO | ECHONL | ISIG);
@@ -1308,7 +1382,7 @@
#define _POSIX_VDISABLE '\0'
#endif
new_settings.c_cc[VINTR] = _POSIX_VDISABLE;
- setTermSettings(0, (void *) &new_settings);
+ tcsetattr(STDIN_FILENO, TCSANOW, &new_settings);
/* Now initialize things */
previous_SIGWINCH_handler = signal(SIGWINCH, win_changed);
@@ -1319,11 +1393,6 @@
entry = getpwuid(geteuid());
if (entry) {
- /* If we enter read_line_input for the Nth time,
- * they may be already allocated! Need to free. */
- free(user_buf);
- if (home_pwd_buf != null_str)
- free(home_pwd_buf);
user_buf = xstrdup(entry->pw_name);
home_pwd_buf = xstrdup(entry->pw_dir);
/* They are not freed on exit (too small to bother) */
@@ -1331,12 +1400,12 @@
}
#endif
/* Print out the command prompt */
- parse_prompt(prompt);
+ parse_and_put_prompt(prompt);
while (1) {
fflush(stdout);
- if (safe_read(0, &c, 1) < 1) {
+ if (safe_read(STDIN_FILENO, &c, 1) < 1) {
/* if we can't read input then exit */
goto prepare_to_die;
}
@@ -1411,9 +1480,11 @@
input_backspace();
break;
+#if ENABLE_FEATURE_TAB_COMPLETION
case '\t':
input_tab(&lastWasTab);
break;
+#endif
#if ENABLE_FEATURE_EDITING_FANCY_KEYS
case CTRL('K'):
@@ -1526,7 +1597,7 @@
int nc, sc;
sc = cursor;
prevc = ic;
- if (safe_read(0, &c, 1) < 1)
+ if (safe_read(STDIN_FILENO, &c, 1) < 1)
goto prepare_to_die;
if (c == (prevc & 0xff)) {
/* "cc", "dd" */
@@ -1587,7 +1658,7 @@
put();
break;
case 'r'|vbit:
- if (safe_read(0, &c, 1) < 1)
+ if (safe_read(STDIN_FILENO, &c, 1) < 1)
goto prepare_to_die;
if (c == 0)
beep();
@@ -1610,19 +1681,19 @@
}
#endif
/* escape sequence follows */
- if (safe_read(0, &c, 1) < 1)
+ if (safe_read(STDIN_FILENO, &c, 1) < 1)
goto prepare_to_die;
/* different vt100 emulations */
if (c == '[' || c == 'O') {
vi_case('['|vbit:)
vi_case('O'|vbit:)
- if (safe_read(0, &c, 1) < 1)
+ if (safe_read(STDIN_FILENO, &c, 1) < 1)
goto prepare_to_die;
}
if (c >= '1' && c <= '9') {
unsigned char dummy;
- if (safe_read(0, &dummy, 1) < 1)
+ if (safe_read(STDIN_FILENO, &dummy, 1) < 1)
goto prepare_to_die;
if (dummy != '~')
c = '\0';
@@ -1687,7 +1758,7 @@
#if ENABLE_FEATURE_NONPRINTABLE_INVERSE_PUT
/* Control-V -- Add non-printable symbol */
if (c == CTRL('V')) {
- if (safe_read(0, &c, 1) < 1)
+ if (safe_read(STDIN_FILENO, &c, 1) < 1)
goto prepare_to_die;
if (c == 0) {
beep();
@@ -1727,8 +1798,10 @@
if (break_out) /* Enter is the command terminator, no more input. */
break;
+#if ENABLE_FEATURE_TAB_COMPLETION
if (c != '\t')
lastWasTab = FALSE;
+#endif
}
if (command_len > 0)
@@ -1739,18 +1812,18 @@
command[command_len] = '\0';
}
-#if ENABLE_FEATURE_CLEAN_UP && ENABLE_FEATURE_TAB_COMPLETION
+#if ENABLE_FEATURE_TAB_COMPLETION
free_tab_completion_data();
#endif
-#if ENABLE_FEATURE_EDITING_FANCY_PROMPT
- free((char*)cmdedit_prompt);
-#endif
/* restore initial_settings */
- setTermSettings(STDIN_FILENO, (void *) &initial_settings);
+ tcsetattr(STDIN_FILENO, TCSANOW, &initial_settings);
/* restore SIGWINCH handler */
signal(SIGWINCH, previous_SIGWINCH_handler);
fflush(stdout);
+
+ DEINIT_S();
+
return command_len;
}