moved biggest stack buffers to malloc space, or made their size configurable

(8k of shell line edit buffer is an overkill)

# make ARCH=i386 bloatcheck
function                                             old     new   delta
read_line_input                                     3933    3967     +34
ifaddrlist                                           348     345      -3
do_loadfont                                          208     191     -17
edit_file                                            840     819     -21
.rodata                                           129112  129080     -32
uncompress                                          1305    1268     -37
loadfont_main                                        566     495     -71
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/6 up/down: 34/-181)          Total: -147 bytes

2 files changed, 36 insertions, 24 deletions

diff --git a/editors/Config.in b/editors/Config.in
index fd840ae9a..936004c9b 100644
--- a/editors/Config.in
+++ b/editors/Config.in
@@ -50,6 +50,16 @@ config VI
           learning curve.  If you are not already comfortable with 'vi'
           you may wish to use something else.
 
+config FEATURE_VI_MAX_LEN
+        int "Maximum line length in vi"
+        range 256 16384
+        default 1024
+        depends on VI
+        help
+          vi uses on-stack buffers for intermediate line buffers.
+          You may want to decrease this parameter if your target machine
+          benefits from smaller stack usage.
+
 config FEATURE_VI_COLON
         bool "Enable \":\" colon commands (no \"ex\" mode)"
         default y
diff --git a/editors/vi.c b/editors/vi.c
index cd64aacc9..b961ca5b8 100644
--- a/editors/vi.c
+++ b/editors/vi.c
@@ -32,7 +32,10 @@
 #define Isprint(c) ((unsigned char)(c) >= ' ' && (c) != 0x7f && (unsigned char)(c) != 0x9b)
 #endif
 
-#define MAX_SCR_COLS            BUFSIZ
+enum {
+        MAX_LINELEN = CONFIG_FEATURE_VI_MAX_LEN,
+        MAX_SCR_COLS = CONFIG_FEATURE_VI_MAX_LEN,
+};
 
 // Misc. non-Ascii keys that report an escape sequence
 #define VI_K_UP                 (char)128       // cursor key Up
@@ -545,7 +548,7 @@ static char *get_one_address(char * p, int *addr)	// get colon addr, if present
         char c;
 #endif
 #if ENABLE_FEATURE_VI_SEARCH
-        char *pat, buf[BUFSIZ];
+        char *pat, buf[MAX_LINELEN];
 #endif
 
         *addr = -1;                     // assume no addr
@@ -648,7 +651,7 @@ static void setops(const char *args, const char *opname, int flg_no,
 static void colon(char * buf)
 {
         char c, *orig_buf, *buf1, *q, *r;
-        char *fn, cmd[BUFSIZ], args[BUFSIZ];
+        char *fn, cmd[MAX_LINELEN], args[MAX_LINELEN];
         int i, l, li, ch, b, e;
         int useforce = FALSE, forced = FALSE;
         struct stat st_buf;
@@ -679,8 +682,8 @@ static void colon(char * buf)
         r = end - 1;
         li = count_lines(text, end - 1);
         fn = cfn;                       // default to current file
-        memset(cmd, '\0', BUFSIZ);      // clear cmd[]
-        memset(args, '\0', BUFSIZ);     // clear args[]
+        memset(cmd, '\0', MAX_LINELEN); // clear cmd[]
+        memset(args, '\0', MAX_LINELEN);        // clear args[]
 
         // look for optional address(es)  :.  :1  :1,9   :'q,'a   :%
         buf = get_address(buf, &b, &e);
@@ -763,10 +766,10 @@ static void colon(char * buf)
                 }
                 if (args[0]) {
                         // the user supplied a file name
-                        fn= args;
+                        fn = args;
                 } else if (cfn && cfn[0]) {
                         // no user supplied name- use the current filename
-                        fn= cfn;
+                        fn = cfn;
                         goto vc5;
                 } else {
                         // no user file name, no current name- punt
@@ -1984,8 +1987,7 @@ static void start_new_cmd_q(char c)
         // release old cmd
         free(last_modifying_cmd);
         // get buffer for new cmd
-        last_modifying_cmd = xmalloc(BUFSIZ);
-        memset(last_modifying_cmd, '\0', BUFSIZ);       // clear new cmd queue
+        last_modifying_cmd = xzalloc(MAX_LINELEN);
         // if there is a current cmd count put it in the buffer first
         if (cmdcnt > 0)
                 sprintf(last_modifying_cmd, "%d%c", cmdcnt, c);
@@ -2238,7 +2240,7 @@ static char readit(void)	// read (maybe cursor) key from stdin
         if (n <= 0) {
  ri0:
                 // the Q is empty, wait for a typed char
-                n = read(0, readbuffer, BUFSIZ - 1);
+                n = read(0, readbuffer, MAX_LINELEN - 1);
                 if (n < 0) {
                         if (errno == EINTR)
                                 goto ri0;       // interrupted sys call
@@ -2268,9 +2270,9 @@ static char readit(void)	// read (maybe cursor) key from stdin
                         tv.tv_usec = 50000;     // Wait 5/100 seconds- 1 Sec=1000000
 
                         // keep reading while there are input chars and room in buffer
-                        while (select(1, &rfds, NULL, NULL, &tv) > 0 && n <= (BUFSIZ - 5)) {
+                        while (select(1, &rfds, NULL, NULL, &tv) > 0 && n <= (MAX_LINELEN - 5)) {
                                 // read the rest of the ESC string
-                                int r = read(0, (void *) (readbuffer + n), BUFSIZ - n);
+                                int r = read(0, (void *) (readbuffer + n), MAX_LINELEN - n);
                                 if (r > 0) {
                                         n += r;
                                 }
@@ -2305,7 +2307,7 @@ static char readit(void)	// read (maybe cursor) key from stdin
         }
         // remove key sequence from Q
         readed_for_parse -= n;
-        memmove(readbuffer, readbuffer + n, BUFSIZ - n);
+        memmove(readbuffer, readbuffer + n, MAX_LINELEN - n);
         alarm(3);       // we are done waiting for input, turn alarm ON
         return c;
 }
@@ -2340,7 +2342,7 @@ static char get_one_char(void)
                 c = readit();   // get the users input
                 if (last_modifying_cmd != 0) {
                         int len = strlen(last_modifying_cmd);
-                        if (len + 1 >= BUFSIZ) {
+                        if (len >= MAX_LINELEN - 1) {
                                 psbs("last_modifying_cmd overrun");
                         } else {
                                 // add new char to q
@@ -2358,7 +2360,7 @@ static char *get_input_line(const char * prompt) // get input line- use "status
 {
         static char *obufp;
 
-        char buf[BUFSIZ];
+        char buf[MAX_LINELEN];
         char c;
         int i;
 
@@ -2369,7 +2371,7 @@ static char *get_input_line(const char * prompt) // get input line- use "status
         write1(prompt);      // write out the :, /, or ? prompt
 
         i = strlen(buf);
-        while (i < BUFSIZ) {
+        while (i < MAX_LINELEN) {
                 c = get_one_char();     // read user input
                 if (c == '\n' || c == '\r' || c == 27)
                         break;          // is this end of input
@@ -2514,16 +2516,16 @@ static int file_write(char * fn, char * first, char * last)
 //----- Move the cursor to row x col (count from 0, not 1) -------
 static void place_cursor(int row, int col, int opti)
 {
-        char cm1[BUFSIZ];
+        char cm1[MAX_LINELEN];
         char *cm;
 #if ENABLE_FEATURE_VI_OPTIMIZE_CURSOR
-        char cm2[BUFSIZ];
+        char cm2[MAX_LINELEN];
         char *screenp;
-        // char cm3[BUFSIZ];
+        // char cm3[MAX_LINELEN];
         int Rrow = last_row;
 #endif
 
-        memset(cm1, '\0', BUFSIZ - 1);  // clear the buffer
+        memset(cm1, '\0', MAX_LINELEN);  // clear the buffer
 
         if (row < 0) row = 0;
         if (row >= rows) row = rows - 1;
@@ -2539,7 +2541,7 @@ static void place_cursor(int row, int col, int opti)
 #if ENABLE_FEATURE_VI_OPTIMIZE_CURSOR
         //----- find the minimum # of chars to move cursor -------------
         //----- 2.  Try moving with discreet chars (Newline, [back]space, ...)
-        memset(cm2, '\0', BUFSIZ - 1);  // clear the buffer
+        memset(cm2, '\0', MAX_LINELEN);  // clear the buffer
 
         // move to the correct row
         while (row < Rrow) {
@@ -2696,7 +2698,7 @@ static void psb(const char *format, ...)
 
 static void ni(const char * s) // display messages
 {
-        char buf[BUFSIZ];
+        char buf[MAX_LINELEN];
 
         print_literal(buf, s);
         psbs("\'%s\' is not implemented", buf);
@@ -3900,7 +3902,7 @@ static void crash_dummy()
  cd0:
         startrbi = rbi = 0;
         sleeptime = 0;          // how long to pause between commands
-        memset(readbuffer, '\0', BUFSIZ);   // clear the read buffer
+        memset(readbuffer, '\0', MAX_LINELEN);   // clear the read buffer
         // generate a command by percentages
         percent = (int) lrand48() % 100;        // get a number from 0-99
         if (percent < Mp) {     //  Movement commands
@@ -3985,7 +3987,7 @@ static void crash_test()
         static time_t oldtim;
 
         time_t tim;
-        char d[2], msg[BUFSIZ];
+        char d[2], msg[MAX_LINELEN];
 
         msg[0] = '\0';
         if (end < text) {