vi: changes to line addresses for colon commands

Make line addresses behave more like vi:

- Vi allows the user to enter an arbitrary number of addresses,
  though only the last two are used.  This simplifies get_address()
  by reducing the amount of state that needs to be carried.

- When a command requires a single address the last one entered is
  used.

- If addresses are separated by a ';' instead of a ',' the current
  line is updated to the left address.  This may be useful when a
  search is used to specify a range, e.g. ':/first/;/last/d'.

- When the last address is empty it should refer to the current line.

function                                             old     new   delta
colon                                               3855    3834     -21
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-21)             Total: -21 bytes

Signed-off-by: Ron Yorston <rmy@pobox.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 60 insertions, 50 deletions

diff --git a/editors/vi.c b/editors/vi.c
index caf01acd3..77c42641e 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -2473,37 +2473,43 @@ static char *get_one_address(char *p, int *result)	// get colon addr, if present
         return p;
 }
 
-# define GET_FIRST  0
-# define GET_SECOND 1
-# define GOT_FIRST  2
-# define GOT_SECOND 3
-# define GOT 2
+# define GET_ADDRESS   0
+# define GET_SEPARATOR 1
 
-static char *get_address(char *p, int *b, int *e)       // get two colon addrs, if present
+// Read line addresses for a colon command.  The user can enter as
+// many as they like but only the last two will be used.
+static char *get_address(char *p, int *b, int *e)
 {
-        int state = GET_FIRST;
+        int state = GET_ADDRESS;
+        char *save_dot = dot;
 
         //----- get the address' i.e., 1,3   'a,'b  -----
         for (;;) {
                 if (isblank(*p)) {
                         p++;
-                } else if (*p == '%' && state == GET_FIRST) {   // alias for 1,$
+                } else if (*p == '%' && state == GET_ADDRESS) { // alias for 1,$
                         p++;
                         *b = 1;
                         *e = count_lines(text, end-1);
-                        state = GOT_SECOND;
-                } else if (*p == ',' && state == GOT_FIRST) {
+                        state = GET_SEPARATOR;
+                } else if (state == GET_SEPARATOR && (*p == ',' || *p == ';')) {
+                        if (*p == ';')
+                                dot = find_line(*e);
                         p++;
-                        state = GET_SECOND;
-                } else if (state == GET_FIRST || state == GET_SECOND) {
-                        p = get_one_address(p, state == GET_FIRST ? b : e);
+                        *b = *e;
+                        state = GET_ADDRESS;
+                } else if (state == GET_ADDRESS) {
+                        p = get_one_address(p, e);
                         if (p == NULL)
                                 break;
-                        state |= GOT;
+                        state = GET_SEPARATOR;
                 } else {
+                        if (state == GET_SEPARATOR && *e < 0)
+                                *e = count_lines(text, dot);
                         break;
                 }
         }
+        dot = save_dot;
         return p;
 }
 
@@ -2637,8 +2643,6 @@ static void colon(char *buf)
 
         li = i = 0;
         b = e = -1;
-        q = text;                       // assume 1,$ for the range
-        r = end - 1;
         li = count_lines(text, end - 1);
         fn = current_filename;
 
@@ -2673,27 +2677,33 @@ static void colon(char *buf)
                 useforce = TRUE;
                 *buf1 = '\0';   // get rid of !
         }
-        if (b >= 0) {
-                // if there is only one addr, then the addr
-                // is the line number of the single line the
-                // user wants. So, reset the end
-                // pointer to point at end of the "b" line
-                q = find_line(b);       // what line is #b
-                r = end_line(q);
-                li = 1;
-        }
-        if (e >= 0) {
-                // we were given two addrs.  change the
-                // end pointer to the addr given by user.
-                r = find_line(e);       // what line is #e
-                r = end_line(r);
-                li = e - b + 1;
+        // assume the command will want a range, certain commands
+        // (read, substitute) need to adjust these assumptions
+        if (e < 0) {
+                q = text;                       // no addr, use 1,$ for the range
+                r = end - 1;
+        } else {
+                // at least one addr was given, get its details
+                q = r = find_line(e);
+                if (b < 0) {
+                        // if there is only one addr, then it's the line
+                        // number of the single line the user wants.
+                        // Reset the end pointer to the end of that line.
+                        r = end_line(q);
+                        li = 1;
+                } else {
+                        // we were given two addrs.  change the
+                        // start pointer to the addr given by user.
+                        q = find_line(b);       // what line is #b
+                        r = end_line(r);
+                        li = e - b + 1;
+                }
         }
         // ------------ now look for the command ------------
         i = strlen(cmd);
         if (i == 0) {           // :123CR goto line #123
-                if (b >= 0) {
-                        dot = find_line(b);     // what line is #b
+                if (e >= 0) {
+                        dot = find_line(e);     // what line is #e
                         dot_skip_over_ws();
                 }
         }
@@ -2711,12 +2721,12 @@ static void colon(char *buf)
         }
 # endif
         else if (cmd[0] == '=' && !cmd[1]) {    // where is the address
-                if (b < 0) {    // no addr given- use defaults
-                        b = e = count_lines(text, dot);
+                if (e < 0) {    // no addr given- use defaults
+                        e = count_lines(text, dot);
                 }
-                status_line("%d", b);
+                status_line("%d", e);
         } else if (strncmp(cmd, "delete", i) == 0) {    // delete lines
-                if (b < 0) {    // no addr given- use defaults
+                if (e < 0) {    // no addr given- use defaults
                         q = begin_line(dot);    // assume .,. for the range
                         r = end_line(dot);
                 }
@@ -2767,7 +2777,7 @@ static void colon(char *buf)
                         li, (int)(end - text)
                 );
         } else if (strncmp(cmd, "file", i) == 0) {      // what File is this
-                if (b != -1 || e != -1) {
+                if (e >= 0) {
                         status_line_bold("No address allowed on this command");
                         goto ret;
                 }
@@ -2787,7 +2797,7 @@ static void colon(char *buf)
                 rawmode();
                 Hit_Return();
         } else if (strncmp(cmd, "list", i) == 0) {      // literal print line
-                if (b < 0) {    // no addr given- use defaults
+                if (e < 0) {    // no addr given- use defaults
                         q = begin_line(dot);    // assume .,. for the range
                         r = end_line(dot);
                 }
@@ -2861,12 +2871,12 @@ static void colon(char *buf)
                         status_line_bold("No filename given");
                         goto ret;
                 }
-                if (b < 0) {    // no addr given- use defaults
-                        q = begin_line(dot);    // assume "dot"
-                }
-                // read after current line- unless user said ":0r foo"
-                if (b != 0) {
-                        q = next_line(q);
+                if (e < 0) {    // no addr given- read after current line
+                        q = begin_line(dot);
+                } else if (e == 0) {    // user said ":0r foo"
+                        q = text;
+                } else {        // addr given- read after that line
+                        q = next_line(find_line(e));
                         // read after last line
                         if (q == end-1)
                                 ++q;
@@ -2969,13 +2979,13 @@ static void colon(char *buf)
                 }
                 len_R = strlen(R);
 
-                q = begin_line(q);
-                if (b < 0) {    // maybe :s/foo/bar/
+                if (e < 0) {    // no addr given
                         q = begin_line(dot);      // start with cur line
-                        b = count_lines(text, q); // cur line number
+                        r = end_line(dot);
+                        b = e = count_lines(text, q); // cur line number
+                } else if (b < 0) {     // one addr given
+                        b = e;
                 }
-                if (e < 0)
-                        e = b;          // maybe :.s/foo/bar/
 
                 for (i = b; i <= e; i++) {      // so, :20,23 s \0 find \0 replace \0
                         char *ls = q;           // orig line start