some combinations of status line and screen refresh don't give a

correct screen, and bug 215 reports trouble with the status line
on small screens.

with this change a) the status line should always be refreshed
properly, b) the status line is a little shorter than it used to
be ("I" instead of "--INSERT--"), c) the status line will be
truncated if it doesn't fit on the screen, and d) if the screen
is too narrow for an error or transient status message (from
psb() or psbs()), then that message will be followed by a "Hit
Return" prompt.  (it wasn't until i did this last bit that the
size grew.  with this, these changes add about 150 bytes.)

- pgf



git-svn-id: svn://busybox.net/trunk/busybox@11477 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 112 insertions, 76 deletions

diff --git a/editors/vi.c b/editors/vi.c
index 374d161d1..ae86b7233 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -166,8 +166,9 @@ static int vi_setops;
 
 
 static int editing;             // >0 while we are editing a file
-static int cmd_mode;            // 0=command  1=insert
+static int cmd_mode;            // 0=command  1=insert 2=replace
 static int file_modified;       // buffer contents changed
+static int last_file_modified = -1;
 static int fn_start;            // index of first cmd line file name
 static int save_argc;           // how many file names on cmd line
 static int cmdcnt;              // repetition count
@@ -176,6 +177,9 @@ static struct timeval tv;	// use select() for small sleeps
 static int rows, columns;       // the terminal screen is this size
 static int crow, ccol, offset;  // cursor is on Crow x Ccol with Horz Ofset
 static Byte *status_buffer;     // mesages to the user
+#define STATUS_BUFFER_LEN  200
+static int have_status_msg;     // is default edit status needed?
+static int last_status_cksum;   // hash of current status line
 static Byte *cfn;               // previous, current, and next file name
 static Byte *text, *end, *textend;      // pointers to the user data in memory
 static Byte *screen;            // pointer to the virtual screen buffer
@@ -272,7 +276,7 @@ static void show_status_line(void);	// put a message on the bottom line
 static void psb(const char *, ...);     // Print Status Buf
 static void psbs(const char *, ...);    // Print Status Buf in standout mode
 static void ni(Byte *);         // display messages
-static void edit_status(void);  // show file status on status line
+static int format_edit_status(void);    // format file status on status line
 static void redraw(int);        // force a full screen refresh
 static void format_line(Byte*, Byte*, int);
 static void refresh(int);       // update the terminal from screen[]
@@ -331,7 +335,7 @@ static void write1(const char *out)
 extern int vi_main(int argc, char **argv)
 {
         int c;
-        RESERVE_CONFIG_BUFFER(STATUS_BUFFER, 200);
+        RESERVE_CONFIG_BUFFER(STATUS_BUFFER, STATUS_BUFFER_LEN);
 
 #ifdef CONFIG_FEATURE_VI_YANKMARK
         int i;
@@ -344,7 +348,7 @@ extern int vi_main(int argc, char **argv)
 #endif                                                  /* CONFIG_FEATURE_VI_CRASHME */
 
         status_buffer = STATUS_BUFFER;
-        *status_buffer = '\0';  // clear status buffer
+        last_status_cksum = 0;
 
 #ifdef CONFIG_FEATURE_VI_READONLY
         vi_readonly = readonly = FALSE;
@@ -450,7 +454,8 @@ static void edit_file(Byte * fn)
         if (ch < 1) {
                 (void) char_insert(text, '\n'); // start empty buf with dummy line
         }
-        file_modified = FALSE;
+        file_modified = 0;
+        last_file_modified = -1;
 #ifdef CONFIG_FEATURE_VI_YANKMARK
         YDreg = 26;                     // default Yank/Delete reg
         Ureg = 27;                      // hold orig line for "U" cmd
@@ -506,7 +511,6 @@ static void edit_file(Byte * fn)
         adding2q = 0;
 #endif                                                  /* CONFIG_FEATURE_VI_DOT_CMD */
         redraw(FALSE);                  // dont force every col re-draw
-        edit_status();
         show_status_line();
 
         //------This is the main Vi cmd handling loop -----------------------
@@ -834,7 +838,8 @@ static void colon(Byte * buf)
                         (void) char_insert(text, '\n');
                         ch= 1;
                 }
-                file_modified = FALSE;
+                file_modified = 0;
+                last_file_modified = -1;
 #ifdef CONFIG_FEATURE_VI_YANKMARK
                 if (Ureg >= 0 && Ureg < 28 && reg[Ureg] != 0) {
                         free(reg[Ureg]);        //   free orig line reg- for 'U'
@@ -871,8 +876,7 @@ static void colon(Byte * buf)
                         cfn = (Byte *) bb_xstrdup((char *) args);
                 } else {
                         // user wants file status info
-                        edit_status();
-                        show_status_line();
+                        last_status_cksum = 0;  // force status update
                 }
         } else if (strncasecmp((char *) cmd, "features", i) == 0) {     // what features are available
                 // print out values of all features
@@ -978,7 +982,7 @@ static void colon(Byte * buf)
                         // if the insert is before "dot" then we need to update
                         if (q <= dot)
                                 dot += ch;
-                        file_modified = TRUE;
+                        file_modified++;
                 }
         } else if (strncasecmp((char *) cmd, "rewind", i) == 0) {       // rewind cmd line args
                 if (file_modified && ! useforce) {
@@ -1109,8 +1113,10 @@ static void colon(Byte * buf)
                         forced = FALSE;
                 }
                 psb("\"%s\" %dL, %dC", fn, li, l);
-                if (q == text && r == end - 1 && l == ch)
-                        file_modified = FALSE;
+                if (q == text && r == end - 1 && l == ch) {
+                        file_modified = 0;
+                        last_file_modified = -1;
+                }
                 if ((cmd[0] == 'x' || cmd[1] == 'q') && l == ch) {
                         editing = 0;
                 }
@@ -1335,30 +1341,22 @@ static void dot_left(void)
 {
         if (dot > text && dot[-1] != '\n')
                 dot--;
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_right(void)
 {
         if (dot < end - 1 && *dot != '\n')
                 dot++;
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_begin(void)
 {
         dot = begin_line(dot);  // return pointer to first char cur line
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_end(void)
 {
         dot = end_line(dot);    // return pointer to last char cur line
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static Byte *move_to_col(Byte * p, int l)
@@ -1383,15 +1381,11 @@ static Byte *move_to_col(Byte * p, int l)
 static void dot_next(void)
 {
         dot = next_line(dot);
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_prev(void)
 {
         dot = prev_line(dot);
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_scroll(int cnt, int dir)
@@ -1416,8 +1410,6 @@ static void dot_scroll(int cnt, int dir)
         if (dot > q)
                 dot = begin_line(q);    // is dot is below bottom line?
         dot_skip_over_ws();
-        edit_status();                  // show current file status
-        show_status_line();
 }
 
 static void dot_skip_over_ws(void)
@@ -1603,12 +1595,12 @@ static Byte *char_insert(Byte * p, Byte c) // insert the char c at 'p'
                 c = get_one_char();
                 *p = c;
                 p++;
-                file_modified = TRUE;   // has the file been modified
+                file_modified++;        // has the file been modified
         } else if (c == 27) {   // Is this an ESC?
                 cmd_mode = 0;
                 cmdcnt = 0;
                 end_cmd_q();    // stop adding to q
-                *status_buffer = '\0';  // clear the status buffer
+                last_status_cksum = 0;  // force status update
                 if ((p[-1] != '\n') && (dot>text)) {
                         p--;
                 }
@@ -1658,7 +1650,7 @@ static Byte *stupid_insert(Byte * p, Byte c) // stupidly insert the char c at 'p
         p = text_hole_make(p, 1);
         if (p != 0) {
                 *p = c;
-                file_modified = TRUE;   // has the file been modified
+                file_modified++;        // has the file been modified
                 p++;
         }
         return (p);
@@ -1856,7 +1848,7 @@ static Byte *text_hole_make(Byte * p, int size)	// at "p", make a 'size' byte ho
         }
         memset(p, ' ', size);   // clear new hole
         end = end + size;       // adjust the new END
-        file_modified = TRUE;   // has the file been modified
+        file_modified++;        // has the file been modified
   thm0:
         return (p);
 }
@@ -1892,7 +1884,7 @@ static Byte *text_hole_delete(Byte * p, Byte * q) // delete "p" thru "q", inclus
                 dest = end - 1; // make sure dest in below end-1
         if (end <= text)
                 dest = end = text;      // keep pointers valid
-        file_modified = TRUE;   // has the file been modified
+        file_modified++;        // has the file been modified
   thd0:
         return (dest);
 }
@@ -2162,7 +2154,7 @@ static void winch_sig(int sig)
 static void cont_sig(int sig)
 {
         rawmode();                      // terminal to "raw"
-        *status_buffer = '\0';  // clear the status buffer
+        last_status_cksum = 0;  // force status update
         redraw(TRUE);           // re-draw the screen
 
         signal(SIGTSTP, suspend_sig);
@@ -2407,7 +2399,7 @@ static Byte *get_input_line(Byte * prompt) // get input line- use "status line"
         static Byte *obufp = NULL;
 
         strcpy((char *) buf, (char *) prompt);
-        *status_buffer = '\0';  // clear the status buffer
+        last_status_cksum = 0;  // force status update
         place_cursor(rows - 1, 0, FALSE);       // go to Status line, bottom of screen
         clear_to_eol();         // clear the line
         write1(prompt);      // write out the :, /, or ? prompt
@@ -2512,7 +2504,7 @@ static int file_insert(Byte * fn, Byte * p, int size)
                 psbs("could not read all of file \"%s\"", fn);
         }
         if (cnt >= size)
-                file_modified = TRUE;
+                file_modified++;
   fi0:
         return (cnt);
 }
@@ -2670,28 +2662,46 @@ static void screen_erase(void)
         memset(screen, ' ', screensize);        // clear new screen
 }
 
+static int bufsum(char *buf, int count)
+{
+        int sum = 0;
+        char *e = buf + count;
+        while (buf < e)
+                sum += *buf++;
+        return sum;
+}
+
 //----- Draw the status line at bottom of the screen -------------
 static void show_status_line(void)
 {
-        static int last_cksum;
-        int l, cnt, cksum;
+        int cnt, cksum;
 
-        //edit_status();
-        cnt = strlen((char *) status_buffer);
-        for (cksum= l= 0; l < cnt; l++) { cksum += (int)(status_buffer[l]); }
-        // don't write the status line unless it changes
-        if (cnt > 0 && last_cksum != cksum) {
-                last_cksum= cksum;              // remember if we have seen this line
+        // either we already have an error or status message, or we
+        // create one.
+        if (!have_status_msg) {
+                cnt = format_edit_status();
+                cksum = bufsum(status_buffer, cnt);
+        }
+        if (have_status_msg || ((cnt > 0 && last_status_cksum != cksum))) {
+                last_status_cksum= cksum;               // remember if we have seen this line
                 place_cursor(rows - 1, 0, FALSE);       // put cursor on status line
                 write1(status_buffer);
                 clear_to_eol();
+                if (have_status_msg) {
+                        if ((strlen(status_buffer) - (have_status_msg - 1)) >
+                                        (columns - 1) ) {
+                                have_status_msg = 0;
+                                Hit_Return();
+                        }
+                        have_status_msg = 0;
+                }
                 place_cursor(crow, ccol, FALSE);        // put cursor back in correct place
         }
         fflush(stdout);
 }
 
 //----- format the status buffer, the bottom line of screen ------
-// print status buffer, with STANDOUT mode
+// format status buffer, with STANDOUT mode
 static void psbs(const char *format, ...)
 {
         va_list args;
@@ -2701,12 +2711,13 @@ static void psbs(const char *format, ...)
         vsprintf((char *) status_buffer + strlen((char *) status_buffer), format, args);
         strcat((char *) status_buffer, SOn);    // Terminal standout mode off
         va_end(args);
-        show_status_line();
+
+        have_status_msg = 1 + sizeof(SOs) + sizeof(SOn) - 2;
 
         return;
 }
 
-// print status buffer
+// format status buffer
 static void psb(const char *format, ...)
 {
         va_list args;
@@ -2714,7 +2725,9 @@ static void psb(const char *format, ...)
         va_start(args, format);
         vsprintf((char *) status_buffer, format, args);
         va_end(args);
-        show_status_line();
+
+        have_status_msg = 1;
+
         return;
 }
 
@@ -2726,12 +2739,28 @@ static void ni(Byte * s) // display messages
         psbs("\'%s\' is not implemented", buf);
 }
 
-static void edit_status(void)   // show file status on status line
+static int format_edit_status(void)     // show file status on status line
 {
-        int cur, tot, percent;
+        int cur, percent, ret, trunc_at;
+        static int tot;
 
+        // file_modified is now a counter rather than a flag.  this
+        // helps reduce the amount of line counting we need to do.
+        // (this will cause a mis-reporting of modified status
+        // once every MAXINT editing operations.)
+
+        // it would be nice to do a similar optimization here -- if
+        // we haven't done a motion that could have changed which line
+        // we're on, then we shouldn't have to do this count_lines()
         cur = count_lines(text, dot);
-        tot = count_lines(text, end - 1);
+
+        // reduce counting -- the total lines can't have
+        // changed if we haven't done any edits.
+        if (file_modified != last_file_modified) {
+                tot = cur + count_lines(dot, end - 1) - 1;
+                last_file_modified = file_modified;
+        }
+
         //    current line         percent
         //   -------------    ~~ ----------
         //    total lines            100
@@ -2742,18 +2771,27 @@ static void edit_status(void)	// show file status on status line
                 percent = 100;
         }
 
-        sprintf((char *) status_buffer,
-                        "\"%s\""
+        trunc_at = columns < STATUS_BUFFER_LEN-1 ?
+                columns : STATUS_BUFFER_LEN-1;
+
+        ret = snprintf((char *) status_buffer, trunc_at+1,
 #ifdef CONFIG_FEATURE_VI_READONLY
-                        "%s"
-#endif                                                  /* CONFIG_FEATURE_VI_READONLY */
-                        "%s line %d of %d --%d%%--",
-                        (cfn != 0 ? (char *) cfn : "No file"),
+                "%c %s%s%s %d/%d %d%%",
+#else
+                "%c %s%s %d/%d %d%%",
+#endif
+                (cmd_mode ? (cmd_mode == 2 ? 'R':'I'):'-'),
+                (cfn != 0 ? (char *) cfn : "No file"),
 #ifdef CONFIG_FEATURE_VI_READONLY
-                        ((vi_readonly || readonly) ? " [Read only]" : ""),
-#endif                                                  /* CONFIG_FEATURE_VI_READONLY */
-                        (file_modified ? " [modified]" : ""),
-                        cur, tot, percent);
+                ((vi_readonly || readonly) ? " [Read-only]" : ""),
+#endif
+                (file_modified ? " [modified]" : ""),
+                cur, tot, percent);
+
+        if (ret >= 0 && ret < trunc_at)
+                return ret;  /* it all fit */
+
+        return trunc_at;  /* had to truncate */
 }
 
 //----- Force refresh of all Lines -----------------------------
@@ -2762,7 +2800,9 @@ static void redraw(int full_screen)
         place_cursor(0, 0, FALSE);      // put cursor in correct place
         clear_to_eos();         // tel terminal to erase display
         screen_erase();         // erase the internal screen buffer
+        last_status_cksum = 0;  // force status update
         refresh(full_screen);   // this will redraw the entire display
+        show_status_line();
 }
 
 //----- Format a text[] line into a buffer ---------------------
@@ -2899,8 +2939,6 @@ static void refresh(int full_screen)
 #endif                                                  /* CONFIG_FEATURE_VI_OPTIMIZE_CURSOR */
                         }
 
-                        edit_status();                  // show current file status
-                        show_status_line();
                         // write line out to terminal
                         {
                                 int nic = ce-cs+1;
@@ -2960,6 +2998,8 @@ static void do_cmd(Byte c)
         p = q = save_dot = msg = buf;   // quiet the compiler
         memset(buf, '\0', 9);   // clear buf
 
+        show_status_line();
+
         /* if this is a cursor key, skip these checks */
         switch (c) {
                 case VI_K_UP:
@@ -3079,8 +3119,7 @@ key_cmd_mode:
                 dot_scroll(rows - 2, 1);
                 break;
         case 7:                 // ctrl-G  show current status
-                edit_status();
-                show_status_line();
+                last_status_cksum = 0;  // force status update
                 break;
         case 'h':                       // h- move left
         case VI_K_LEFT: // cursor key Left
@@ -3090,8 +3129,6 @@ key_cmd_mode:
                         do_cmd(c);
                 }                               // repeat cnt
                 dot_left();
-                edit_status();                  // show current file status
-                show_status_line();
                 break;
         case 10:                        // Newline ^J
         case 'j':                       // j- goto next line, same col
@@ -3108,6 +3145,7 @@ key_cmd_mode:
                 clear_to_eos(); // tel terminal to erase display
                 (void) mysleep(10);
                 screen_erase(); // erase the internal screen buffer
+                last_status_cksum = 0;  // force status update
                 refresh(TRUE);  // this will redraw the entire display
                 break;
         case 13:                        // Carriage Return ^M
@@ -3129,7 +3167,7 @@ key_cmd_mode:
                         indicate_error(c);
                 cmd_mode = 0;   // stop insrting
                 end_cmd_q();
-                *status_buffer = '\0';  // clear status buffer
+                last_status_cksum = 0;  // force status update
                 break;
         case ' ':                       // move right
         case 'l':                       // move right
@@ -3349,7 +3387,7 @@ key_cmd_mode:
                         msg = (Byte *) "Pattern not found";
                 }
           dc2:
-                psbs("%s", msg);
+                if (*msg) psbs("%s", msg);
                 break;
         case '{':                       // {- move backward paragraph
                 q = char_search(dot, (Byte *) "\n\n", BACK, FULL);
@@ -3401,14 +3439,14 @@ key_cmd_mode:
                                    strncasecmp((char *) p, "wq", cnt) == 0 ||
                                    strncasecmp((char *) p, "x", cnt) == 0) {
                         cnt = file_write(cfn, text, end - 1);
-                        file_modified = FALSE;
+                        file_modified = 0;
+                        last_file_modified = -1;
                         psb("\"%s\" %dL, %dC", cfn, count_lines(text, end - 1), cnt);
                         if (p[0] == 'x' || p[1] == 'q') {
                                 editing = 0;
                         }
                 } else if (strncasecmp((char *) p, "file", cnt) == 0 ) {
-                        edit_status();                  // show current file status
-                        show_status_line();
+                        last_status_cksum = 0;  // force status update
                 } else if (sscanf((char *) p, "%d", &j) > 0) {
                         dot = find_line(j);             // go to line # j
                         dot_skip_over_ws();
@@ -3509,7 +3547,6 @@ key_cmd_mode:
         case VI_K_INSERT:       // Cursor Key Insert
           dc_i:
                 cmd_mode = 1;   // start insrting
-                psb("-- Insert --");
                 break;
         case 'J':                       // J- join current and next lines together
                 if (cmdcnt-- > 2) {
@@ -3518,7 +3555,7 @@ key_cmd_mode:
                 dot_end();              // move to NL
                 if (dot < end - 1) {    // make sure not last char in text[]
                         *dot++ = ' ';   // replace NL with space
-                        file_modified = TRUE;
+                        file_modified++;
                         while (isblnk(*dot)) {  // delete leading WS
                                 dot_delete();
                         }
@@ -3559,7 +3596,6 @@ key_cmd_mode:
         case 'R':                       // R- continuous Replace char
           dc5:
                 cmd_mode = 2;
-                psb("-- Replace --");
                 break;
         case 'X':                       // X- delete char before dot
         case 'x':                       // x- delete the current char
@@ -3709,7 +3745,7 @@ key_cmd_mode:
                 c1 = get_one_char();    // get the replacement char
                 if (*dot != '\n') {
                         *dot = c1;
-                        file_modified = TRUE;   // has the file been modified
+                        file_modified++;        // has the file been modified
                 }
                 end_cmd_q();    // stop adding to q
                 break;
@@ -3754,10 +3790,10 @@ key_cmd_mode:
                 }                               // repeat cnt
                 if (islower(*dot)) {
                         *dot = toupper(*dot);
-                        file_modified = TRUE;   // has the file been modified
+                        file_modified++;        // has the file been modified
                 } else if (isupper(*dot)) {
                         *dot = tolower(*dot);
-                        file_modified = TRUE;   // has the file been modified
+                        file_modified++;        // has the file been modified
                 }
                 dot_right();
                 end_cmd_q();    // stop adding to q