fs_cli: do not assume that LineInfo buffers are null-terminated

man editline(3el) says that they're not.

[take #2, originally was 48acc0cd387f90390ba2a7a6435e02b2f4866336]

diff --git a/libs/esl/fs_cli.c b/libs/esl/fs_cli.c
index 98724c3696032aa48db73c90f5c265d2be5c4421..6bc96e27e18710f9b4d04a24cc5f9d659a3cbff7 100644 (file)
--- a/libs/esl/fs_cli.c
+++ b/libs/esl/fs_cli.c
@@ -861,17 +861,25 @@ static void set_fn_keys(cli_profile_t *profile)
 
 static char* end_of_str(char *s) { return (*s == '\0' ? s : s + strlen(s) - 1); }
 
-static unsigned char esl_console_complete(const char *buffer, const char *cursor)
+static char* _strndup(const char *s, int n)
+{
+       char *r = (char*)malloc(n + 1), *d=r;
+       while (n > 0 && *s) {
+               *d = *s;
+               d++; s++; n--;
+       }
+       *d = 0;
+       return r;
+}
+
+static unsigned char esl_console_complete(const char *buffer, const char *cursor, const char *lastchar)
 {
        char cmd_str[2048] = "";
        unsigned char ret = CC_REDISPLAY;
-       char *dup = strdup(buffer);
+       char *dup = _strndup(buffer, (lastchar - buffer));
        char *buf = dup;
-       int pos = 0, sc = 0;
+       int sc = 0, offset = (int)(cursor - buffer), pos = (offset > 0) ? offset : 0;
        char *p;
-       if (!esl_strlen_zero(cursor) && !esl_strlen_zero(buffer)) {
-               pos = (int)(cursor - buffer);
-       }
        if (pos > 0) {
                *(buf + pos) = '\0';
        }
@@ -944,7 +952,7 @@ static unsigned char esl_console_complete(const char *buffer, const char *cursor
 static unsigned char complete(EditLine *el, int ch)
 {
        const LineInfo *lf = el_line(el);
-       return esl_console_complete(lf->buffer, lf->cursor);
+       return esl_console_complete(lf->buffer, lf->cursor, lf->lastchar);
 }
 #endif
 
@@ -1035,6 +1043,15 @@ static void read_config(const char *dft_cfile, const char *cfile) {
        }
 }
 
+static void clear_el_buffer(void) {
+#ifdef HAVE_EDITLINE
+       const LineInfo *lf = el_line(el);
+       int len = (int)(lf->lastchar - lf->buffer);
+       el_deletestr(el, len);
+       memset((char*)lf->buffer, 0, len);
+#endif
+}
+
 int main(int argc, char *argv[])
 {
        esl_handle_t handle = {{0}};
@@ -1355,14 +1372,7 @@ int main(int argc, char *argv[])
                                running = r;
                        }
                        free(cmd);
-#ifdef HAVE_EDITLINE
-                       {
-                               const LineInfo *lf = el_line(el);
-                               char *s = (char *) lf->buffer;
-                               el_deletestr(el, strlen(s) + 1);
-                               memset(s, 0, strlen(s));
-                       }
-#endif
+                       clear_el_buffer();
                }
                sleep_ms(1);
        }