last_patch_68 from Vladimir N. Oleynik

git-svn-id: svn://busybox.net/trunk/busybox@6028 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 62 insertions, 100 deletions

diff --git a/shell/cmdedit.c b/shell/cmdedit.c
index eee32131a..b6e743eb4 100644
--- a/shell/cmdedit.c
+++ b/shell/cmdedit.c
@@ -89,22 +89,17 @@
 #endif                                                  /* advanced FEATURES */
 
 
-
-struct history {
-        char *s;
-        struct history *p;
-        struct history *n;
-};
-
 /* Maximum length of the linked list for the command line history */
-static const int MAX_HISTORY = 15;
-
-/* First element in command line list */
-static struct history *his_front = NULL;
-
-/* Last element in command line list */
-static struct history *his_end = NULL;
-
+#define MAX_HISTORY 15
+#if MAX_HISTORY < 1
+#warning cmdedit: You set MAX_HISTORY < 1. The history algorithm switched off.
+#else
+static char *history[MAX_HISTORY+1]; /* history + current */
+/* saved history lines */
+static int n_history;
+/* current pointer to history line */
+static int cur_history;
+#endif
 
 #include <termios.h>
 #define setTermSettings(fd,argp) tcsetattr(fd,TCSANOW,argp)
@@ -116,7 +111,6 @@ static struct termios initial_settings, new_settings;
 
 static
 volatile int cmdedit_termw = 80;        /* actual terminal width */
-static int history_counter = 0; /* Number of commands in history list */
 static
 volatile int handlers_sets = 0; /* Set next bites: */
 
@@ -148,7 +142,7 @@ static int my_euid;
 #endif
 
 #ifdef CONFIG_FEATURE_SH_FANCY_PROMPT
-static char *hostname_buf = "";
+static char *hostname_buf;
 static int num_ok_lines = 1;
 #endif
 
@@ -207,19 +201,6 @@ static void cmdedit_reset_term(void)
                 handlers_sets &= ~SET_WCHG_HANDLERS;
         }
         fflush(stdout);
-#if 0
-//#ifdef CONFIG_FEATURE_CLEAN_UP
-        if (his_front) {
-                struct history *n;
-
-                while (his_front != his_end) {
-                        n = his_front->n;
-                        free(his_front->s);
-                        free(his_front);
-                        his_front = n;
-                }
-        }
-#endif
 }
 
 
@@ -368,7 +349,7 @@ static void parse_prompt(const char *prmt_ptr)
 #endif  
                           case 'h':
                                 pbuf = hostname_buf;
-                                if (*pbuf == 0) {
+                                if (pbuf == 0) {
                                         pbuf = xcalloc(256, 1);
                                         if (gethostname(pbuf, 255) < 0) {
                                                 strcpy(pbuf, "?");
@@ -1122,18 +1103,29 @@ static void input_tab(int *lastWasTab)
 }
 #endif  /* CONFIG_FEATURE_COMMAND_TAB_COMPLETION */
 
-static void get_previous_history(struct history **hp, struct history *p)
+#if MAX_HISTORY >= 1
+static void get_previous_history(void)
 {
-        if ((*hp)->s)
-                free((*hp)->s);
-        (*hp)->s = xstrdup(command_ps);
-        *hp = p;
+        if(command_ps[0] != 0 || history[cur_history] == 0) {
+                free(history[cur_history]);
+                history[cur_history] = xstrdup(command_ps);
+        }
+        cur_history--;
 }
 
-static inline void get_next_history(struct history **hp)
+static int get_next_history(void)
 {
-        get_previous_history(hp, (*hp)->n);
+        int ch = cur_history;
+
+        if (ch < n_history) {
+                get_previous_history(); /* save the current history line */
+                return (cur_history = ch+1);
+        } else {
+                beep();
+                return 0;
+        }
 }
+#endif
 
 enum {
         ESC = 27,
@@ -1165,7 +1157,6 @@ int cmdedit_read_input(char *prompt, char command[BUFSIZ])
         int break_out = 0;
         int lastWasTab = FALSE;
         unsigned char c = 0;
-        struct history *hp = his_end;
 
         /* prepare before init handlers */
         cmdedit_y = 0;  /* quasireal y, not true work if line > xt*yt */
@@ -1271,31 +1262,26 @@ prepare_to_die:
                         printf("\033[J");
                         break;
                 case 12: 
-                        {
                                 /* Control-l -- clear screen */
-                                int old_cursor = cursor;
                                 printf("\033[H");
-                                redraw(0, len-old_cursor);
-                        }
+                        redraw(0, len-cursor);
                         break;
+#if MAX_HISTORY >= 1
                 case 14:
                         /* Control-n -- Get next command in history */
-                        if (hp && hp->n && hp->n->s) {
-                                get_next_history(&hp);
+                        if (get_next_history())
                                 goto rewrite_line;
-                        } else {
-                                beep();
-                        }
                         break;
                 case 16:
                         /* Control-p -- Get previous command from history */
-                        if (hp && hp->p) {
-                                get_previous_history(&hp, hp->p);
+                        if (cur_history > 0) {
+                                get_previous_history();
                                 goto rewrite_line;
                         } else {
                                 beep();
                         }
                         break;
+#endif
                 case 21:
                         /* Control-U -- Clear line before cursor */
                         if (cursor) {
@@ -1319,10 +1305,11 @@ prepare_to_die:
                                 input_tab(&lastWasTab);
                                 break;
 #endif
+#if MAX_HISTORY >= 1
                         case 'A':
                                 /* Up Arrow -- Get previous command from history */
-                                if (hp && hp->p) {
-                                        get_previous_history(&hp, hp->p);
+                                if (cur_history > 0) {
+                                        get_previous_history();
                                         goto rewrite_line;
                                 } else {
                                         beep();
@@ -1330,21 +1317,16 @@ prepare_to_die:
                                 break;
                         case 'B':
                                 /* Down Arrow -- Get next command in history */
-                                if (hp && hp->n && hp->n->s) {
-                                        get_next_history(&hp);
-                                        goto rewrite_line;
-                                } else {
-                                        beep();
-                                }
+                                if (!get_next_history())
                                 break;
-
                                 /* Rewrite the line with the selected history item */
-                          rewrite_line:
+rewrite_line:
                                 /* change command */
-                                len = strlen(strcpy(command, hp->s));
+                                len = strlen(strcpy(command, history[cur_history]));
                                 /* redraw and go to end line */
                                 redraw(cmdedit_y, 0);
                                 break;
+#endif
                         case 'C':
                                 /* Right Arrow -- Move forward one character */
                                 input_forward();
@@ -1428,53 +1410,33 @@ prepare_to_die:
         setTermSettings(0, (void *) &initial_settings);
         handlers_sets &= ~SET_RESET_TERM;
 
+#if MAX_HISTORY >= 1
         /* Handle command history log */
+        /* cleanup may be saved current command line */
+        free(history[MAX_HISTORY]);
+        history[MAX_HISTORY] = 0;
         if (len) {                                      /* no put empty line */
-
-                struct history *h = his_end;
-                char *ss;
-
-                ss = xstrdup(command);  /* duplicate */
-
-                if (h == 0) {
-                        /* No previous history -- this memory is never freed */
-                        h = his_front = xmalloc(sizeof(struct history));
-                        h->n = xmalloc(sizeof(struct history));
-
-                        h->p = NULL;
-                        h->s = ss;
-                        h->n->p = h;
-                        h->n->n = NULL;
-                        h->n->s = NULL;
-                        his_end = h->n;
-                        history_counter++;
-                } else {
-                        /* Add a new history command -- this memory is never freed */
-                        h->n = xmalloc(sizeof(struct history));
-
-                        h->n->p = h;
-                        h->n->n = NULL;
-                        h->n->s = NULL;
-                        h->s = ss;
-                        his_end = h->n;
-
+                int i = n_history;
                         /* After max history, remove the oldest command */
-                        if (history_counter >= MAX_HISTORY) {
-
-                                struct history *p = his_front->n;
-
-                                p->p = NULL;
-                                free(his_front->s);
-                                free(his_front);
-                                his_front = p;
-                        } else {
-                                history_counter++;
-                        }
+                if (i >= MAX_HISTORY) {
+                        free(history[0]);
+                        for(i = 0; i < (MAX_HISTORY-1); i++)
+                                history[i] = history[i+1];
                 }
+                history[i++] = xstrdup(command);
+                cur_history = i;
+                n_history = i;
 #if defined(CONFIG_FEATURE_SH_FANCY_PROMPT)
                 num_ok_lines++;
 #endif
         }
+#else  /* MAX_HISTORY < 1 */
+#if defined(CONFIG_FEATURE_SH_FANCY_PROMPT)
+        if (len) {              /* no put empty line */
+                num_ok_lines++;
+        }
+#endif
+#endif  /* MAX_HISTORY >= 1 */
         if(break_out>0) {
         command[len++] = '\n';          /* set '\n' */
         command[len] = 0;