1 files changed, 89 insertions, 82 deletions

diff --git a/miscutils/less.c b/miscutils/less.c
index 3fd22ca19..1b993ea2c 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -20,26 +20,26 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  * 02111-1307 USA
  *
- *      This program needs a lot of development, so consider it in a beta stage
- *      at best.
+ *      This program needs a lot of development, so consider it in a beta stage
+ *      at best.
  *
- *      TODO:
- *      - Add more regular expression support - search modifiers, certain matches, etc.
- *      - Add more complex bracket searching - currently, nested brackets are
- *      not considered.
- *      - Add support for "F" as an input. This causes less to act in
- *      a similar way to tail -f.
- *      - Check for binary files, and prompt the user if a binary file
- *      is detected.
- *      - Allow horizontal scrolling. Currently, lines simply continue onto
- *      the next line, per the terminal's discretion
+ *      TODO:
+ *      - Add more regular expression support - search modifiers, certain matches, etc.
+ *      - Add more complex bracket searching - currently, nested brackets are
+ *      not considered.
+ *      - Add support for "F" as an input. This causes less to act in
+ *      a similar way to tail -f.
+ *      - Check for binary files, and prompt the user if a binary file
+ *      is detected.
+ *      - Allow horizontal scrolling. Currently, lines simply continue onto
+ *      the next line, per the terminal's discretion
  *
- *      Notes:
- *      - filename is an array and not a pointer because that avoids all sorts
- *      of complications involving the fact that something that is pointed to
- *      will be changed if the pointer is changed.
- *      - the inp file pointer is used so that keyboard input works after
- *      redirected input has been read from stdin
+ *      Notes:
+ *      - filename is an array and not a pointer because that avoids all sorts
+ *      of complications involving the fact that something that is pointed to
+ *      will be changed if the pointer is changed.
+ *      - the inp file pointer is used so that keyboard input works after
+ *      redirected input has been read from stdin
 */
 
 #include <stdio.h>
@@ -77,7 +77,7 @@
 #define NORMAL "\033[0m"
 
 /* The escape code to clear the screen */
-#define CLEAR "\033[2J"
+#define CLEAR "\033[H\033[J"
 
 /* Maximum number of lines in a file */
 #define MAXLINES 10000
@@ -142,13 +142,6 @@ static void set_tty_cooked(void) {
 
 /* Set terminal input to raw mode  (taken from vi.c) */
 static void set_tty_raw(void) {
-       tcgetattr(0, &term_orig);
-        term_vi = term_orig;
-        term_vi.c_lflag &= (~ICANON & ~ECHO);
-        term_vi.c_iflag &= (~IXON & ~ICRNL);
-        term_vi.c_oflag &= (~ONLCR);
-        term_vi.c_cc[VMIN] = 1;
-        term_vi.c_cc[VTIME] = 0;
         tcsetattr(0, TCSANOW, &term_vi);
 }
 
@@ -169,36 +162,34 @@ static void tless_exit(int code) {
    special return codes. Note that this function works best with raw input. */
 static int tless_getch(void) {
 
+        int input;
+
         set_tty_raw();
-        char input_key[3];
 
-        input_key[0] = getc(inp);
+        input = getc(inp);
         /* Detect escape sequences (i.e. arrow keys) and handle
            them accordingly */
 
-        if (input_key[0] == '\033') {
-                input_key[1] = getc(inp);
-                input_key[2] = getc(inp);
+        if (input == '\033' && getc(inp) == '[') {
+                input = getc(inp);
                 set_tty_cooked();
-                if (input_key[1] == '[') {
-                        if (input_key[2] == REAL_KEY_UP)
-                                return KEY_UP;
-                        else if (input_key[2] == REAL_KEY_DOWN)
-                                return KEY_DOWN;
-                        else if (input_key[2] == REAL_KEY_RIGHT)
-                                return KEY_RIGHT;
-                        else if (input_key[2] == REAL_KEY_LEFT)
-                                return KEY_LEFT;
-                        else if (input_key[2] == REAL_PAGE_UP)
-                                return PAGE_UP;
-                        else if (input_key[2] == REAL_PAGE_DOWN)
-                                return PAGE_DOWN;
-                }
+                if (input == REAL_KEY_UP)
+                        return KEY_UP;
+                else if (input == REAL_KEY_DOWN)
+                        return KEY_DOWN;
+                else if (input == REAL_KEY_RIGHT)
+                        return KEY_RIGHT;
+                else if (input == REAL_KEY_LEFT)
+                        return KEY_LEFT;
+                else if (input == REAL_PAGE_UP)
+                        return PAGE_UP;
+                else if (input == REAL_PAGE_DOWN)
+                        return PAGE_DOWN;
         }
         /* The input is a normal ASCII value */
         else {
                 set_tty_cooked();
-                return input_key[0];
+                return input;
         }
         return 0;
 }
@@ -222,8 +213,7 @@ static void add_linenumbers(void) {
 
         for (i = 0; i <= num_flines; i++) {
                 safe_strncpy(current_line, flines[i], 256);
-                flines[i] = xrealloc(flines[i], strlen(current_line) + 7);
-                sprintf(flines[i],"%5d %s", i + 1, current_line);
+                bb_xasprintf(&flines[i],"%5d %s", i + 1, current_line);
         }
 }
 
@@ -241,12 +231,12 @@ static void data_readlines(void) {
         rewind(fp);
         /* Initialise fp */
         flines = malloc(i * sizeof(char *));
-                
+
         for (i = 0; (!feof(fp)) && (i <= MAXLINES); i++) {
                 strcpy(current_line, "");
                 fgets(current_line, 256, fp);
                 bb_xferror(fp, filename);
-                flines[i] = (char *) bb_xstrndup(current_line, (strlen(current_line) + 1) * sizeof(char));
+                flines[i] = bb_xstrdup(current_line);
         }
         num_flines = i - 2;
 
@@ -258,7 +248,7 @@ static void data_readlines(void) {
         fclose(fp);
 
         inp = (inp_stdin) ? fopen(CURRENT_TTY, "r") : stdin;
-        
+
         if (ea_inp_stdin) {
                 fclose(inp);
                 inp = fopen(CURRENT_TTY, "r");
@@ -307,7 +297,7 @@ static void m_status_print(void) {
                 }
                 else {
                         percentage = calc_percent();
-                        printf("%i%s %s", percentage, "%", NORMAL);
+                        printf("%i%% %s", percentage, NORMAL);
                 }
         }
         else {
@@ -325,11 +315,11 @@ static void medium_status_print(void) {
         percentage = calc_percent();
 
         if (!line_pos)
-                printf("%s%s %i%s%s", HIGHLIGHT, filename, percentage, "%", NORMAL);
+                printf("%s%s %i%%%s", HIGHLIGHT, filename, percentage, NORMAL);
         else if (line_pos == num_flines - height + 2)
                 printf("%s(END)%s", HIGHLIGHT, NORMAL);
         else
-                printf("%s%i%s%s", HIGHLIGHT, percentage, "%", NORMAL);
+                printf("%s%i%%%s", HIGHLIGHT, percentage, NORMAL);
 }
 #endif
 
@@ -368,15 +358,12 @@ static void buffer_print(void) {
 
         int i;
 
+        printf("%s", CLEAR);
         if (num_flines >= height - 2) {
-                printf("%s", CLEAR);
-                move_cursor(0,0);
                 for (i = 0; i < height - 1; i++)
                         printf("%s", buffer[i]);
         }
         else {
-                printf("%s", CLEAR);
-                move_cursor(0,0);
                 for (i = 1; i < (height - 1 - num_flines); i++)
                         putchar('\n');
                 for (i = 0; i < height - 1; i++)
@@ -391,9 +378,14 @@ static void buffer_init(void) {
 
         int i;
 
-        /* malloc the number of lines needed for the buffer */
-        buffer = xrealloc(buffer, height * sizeof(char *));
-        
+        if(buffer == NULL) {
+                /* malloc the number of lines needed for the buffer */
+                buffer = xrealloc(buffer, height * sizeof(char *));
+        } else {
+                for (i = 0; i < (height - 1); i++)
+                        free(buffer[i]);
+        }
+
         /* Fill the buffer until the end of the file or the
            end of the buffer is reached */
         for (i = 0; (i < (height - 1)) && (i <= num_flines); i++) {
@@ -402,7 +394,7 @@ static void buffer_init(void) {
 
         /* If the buffer still isn't full, fill it with blank lines */
         for (; i < (height - 1); i++) {
-                buffer[i] = "";
+                buffer[i] = bb_xstrdup("");
         }
 }
 
@@ -414,16 +406,20 @@ static void buffer_down(int nlines) {
         if (!past_eof) {
                 if (line_pos + (height - 3) + nlines < num_flines) {
                         line_pos += nlines;
-                        for (i = 0; i < (height - 1); i++)
+                        for (i = 0; i < (height - 1); i++) {
+                                free(buffer[i]);
                                 buffer[i] = (char *) bb_xstrdup(flines[line_pos + i]);
+                        }
                 }
                 else {
                         /* As the number of lines requested was too large, we just move
                         to the end of the file */
                         while (line_pos + (height - 3) + 1 < num_flines) {
                                 line_pos += 1;
-                                for (i = 0; i < (height - 1); i++)
+                                for (i = 0; i < (height - 1); i++) {
+                                        free(buffer[i]);
                                         buffer[i] = (char *) bb_xstrdup(flines[line_pos + i]);
+                                }
                         }
                 }
 
@@ -441,16 +437,20 @@ static void buffer_up(int nlines) {
         if (!past_eof) {
                 if (line_pos - nlines >= 0) {
                         line_pos -= nlines;
-                        for (i = 0; i < (height - 1); i++)
+                        for (i = 0; i < (height - 1); i++) {
+                                free(buffer[i]);
                                 buffer[i] = (char *) bb_xstrdup(flines[line_pos + i]);
+                        }
                 }
                 else {
                 /* As the requested number of lines to move was too large, we
                    move one line up at a time until we can't. */
                         while (line_pos != 0) {
                                 line_pos -= 1;
-                                for (i = 0; i < (height - 1); i++)
+                                for (i = 0; i < (height - 1); i++) {
+                                        free(buffer[i]);
                                         buffer[i] = (char *) bb_xstrdup(flines[line_pos + i]);
+                                }
                         }
                 }
         }
@@ -469,11 +469,12 @@ static void buffer_up(int nlines) {
                         /* We only move part of the buffer, as the rest
                         is past the EOF */
                         for (i = 0; i < (height - 1); i++) {
+                                free(buffer[i]);
                                 if (i < tilde_line - nlines + 1)
                                         buffer[i] = (char *) bb_xstrdup(flines[line_pos + i]);
                                 else {
                                         if (line_pos >= num_flines - height + 2)
-                                                buffer[i] = "~\n";
+                                                buffer[i] = bb_xstrdup("~\n");
                                 }
                         }
                 }
@@ -491,12 +492,15 @@ static void buffer_line(int linenum) {
                 printf("%s%s%i%s", HIGHLIGHT, "Cannot seek to line number ", linenum, NORMAL);
         }
         else if (linenum < (num_flines - height - 2)) {
-                for (i = 0; i < (height - 1); i++)
+                for (i = 0; i < (height - 1); i++) {
+                        free(buffer[i]);
                         buffer[i] = (char *) bb_xstrdup(flines[linenum + i]);
+                }
                 line_pos = linenum;
         }
         else {
                 for (i = 0; i < (height - 1); i++) {
+                        free(buffer[i]);
                         if (linenum + i < num_flines + 2)
                                 buffer[i] = (char *) bb_xstrdup(flines[linenum + i]);
                         else
@@ -516,7 +520,7 @@ static void reinitialise(void) {
         for (i = 0; i <= num_flines; i++)
                 free(flines[i]);
         free(flines);
-        
+
         data_readlines();
         buffer_init();
         buffer_print();
@@ -629,15 +633,10 @@ static void colon_process(void) {
 
 static char *insert_highlights (char *line, int start, int end) {
 
-        char *new_line = (char *) malloc((sizeof(char) * (strlen(line) + 1)) + 10);
-
-        memset(new_line, 0, ((sizeof(char) * (strlen(line) + 1)) + 10));
-        strncat(new_line, line, start);
-        strcat(new_line, HIGHLIGHT);
-        strncat(new_line, line + start, end - start);
-        strcat(new_line, NORMAL);
-        strncat(new_line, line + end, strlen(line) - end);
+        char *new_line;
 
+        bb_xasprintf(&new_line, "%.*s%s%.*s%s%s", start, line, HIGHLIGHT,
+                        end - start, line + start, NORMAL, line + end);
         return new_line;
 }
 
@@ -652,7 +651,7 @@ static char *process_regex_on_line(char *line, regex_t *pattern) {
         char sub_line[256];
         int prev_eo = 0;
         regmatch_t match_structs;
-        
+
         memset(sub_line, 0, 256);
         strcpy(line2, line);
 
@@ -869,7 +868,7 @@ static void show_flag_status(void) {
         }
 
         clear_line();
-        printf("%s%s%i%s", HIGHLIGHT, "The status of the flag is: ", flag_val, NORMAL);
+        printf("%s%s%i%s", HIGHLIGHT, "The status of the flag is: ", flag_val != 0, NORMAL);
 }
 #endif
 
@@ -940,7 +939,7 @@ static void goto_mark(void) {
         printf("Go to mark: ");
         letter = tless_getch();
         clear_line();
-        
+
         if (isalpha(letter)) {
                 for (i = 0; i <= num_marks; i++)
                         if (letter == mark_lines[i][0]) {
@@ -985,7 +984,7 @@ static void match_right_bracket(char bracket) {
         int i;
 
         clear_line();
-        
+
         if (strchr(flines[line_pos], bracket) == NULL)
                 printf("%s%s%s", HIGHLIGHT, "No bracket in top line", NORMAL);
         else {
@@ -1010,7 +1009,7 @@ static void match_left_bracket (char bracket) {
         int i;
 
         clear_line();
-        
+
         if (strchr(flines[line_pos + height - 2], bracket) == NULL) {
                 printf("%s%s%s", HIGHLIGHT, "No bracket in bottom line", NORMAL);
                 printf("%s", flines[line_pos + height]);
@@ -1168,6 +1167,14 @@ int less_main(int argc, char **argv) {
 
         strcpy(filename, (inp_stdin) ? "stdin" : files[0]);
         tty_width_height();
+        tcgetattr(0, &term_orig);
+        term_vi = term_orig;
+        term_vi.c_lflag &= (~ICANON & ~ECHO);
+        term_vi.c_iflag &= (~IXON & ~ICRNL);
+        term_vi.c_oflag &= (~ONLCR);
+        term_vi.c_cc[VMIN] = 1;
+        term_vi.c_cc[VTIME] = 0;
+
         data_readlines();
         buffer_init();
         buffer_print();