Merge branch 'corruptionfixing'

multiple changes to mitigate the corruption/segfaults:
- rework ext_kill slightly to avoid lockups in edgecases
- rewrite the threading model for preview thread
- no longer (l)stat files on selection

README.md

@@ -9,6 +9,7 @@ another cli filebrowser made just for myself with the following ideas:
 - more respect for `LS_COLORS`
 - no fancy file edit operations, at most drop to shell
 - no fancy in depth configuration besides the scripts
+- minimize hanging due to unneeded disk io
 
 ## keybinds
 ### vim - work mostly as expected

ext/colors.c

@@ -8,6 +8,7 @@
 #include <wchar.h>
 #include <unistd.h>
 #include "colors.h"
+#include "sncurses.h"
 
 void
 init_colors()
@@ -20,7 +21,7 @@ init_colors()
 	 * fg: first 4 bits, bg: last 4 bits */
 	for (int fg = COLOR_DEFAULT; fg <= COLOR_WHITE; ++fg) {
 		for (int bg = COLOR_DEFAULT; bg <= COLOR_WHITE; ++bg) {
-			init_pair(COL(fg, bg), fg, bg);
+			sinit_pair(COL(fg, bg), fg, bg);
 		}
 	}
 }
@@ -150,7 +151,7 @@ mvwaddcolitem(WINDOW *win, int y, int x, const char *name, mode_t mode)
 	}
 
 	if (!getenv("LS_COLORS")) {
-		mvwaddstr(win, y, x-1, fname);
+		smvwaddstr(win, y, x-1, fname);
 		return;
 	}
 
@@ -210,7 +211,7 @@ mvwaddcolitem(WINDOW *win, int y, int x, const char *name, mode_t mode)
 		attrs = find_lsattrs("no");
 	}
 
-	wattron(win, attrs);
-	mvwaddstr(win, y, x-1, fname);
-	wattroff(win, attrs);
+	swattron(win, attrs);
+	smvwaddstr(win, y, x-1, fname);
+	swattroff(win, attrs);
 }

ext/sncurses.c

@@ -0,0 +1,119 @@
+/* sncurses.c
+ * safe(r) ncurses wrappers that should be fine across threads */
+
+#include <ncurses.h>
+#include <pthread.h>
+#include "sncurses.h"
+
+pthread_mutex_t ncurses_lock = PTHREAD_MUTEX_INITIALIZER;
+
+int
+sinit_pair(short pair, short f, short b)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = init_pair(pair, f, b);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+WINDOW *
+snewwin(int nlines, int ncols, int begin_y, int begin_x)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	WINDOW *r = newwin(nlines, ncols, begin_y, begin_x);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+sdelwin(WINDOW *win)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = delwin(win);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+sbox(WINDOW *win, chtype verch, chtype horch)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = box(win, verch, horch);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+swaddch(WINDOW *win, const chtype ch)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = waddch(win, ch);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+smvwaddch(WINDOW *win, int y, int x, const chtype ch)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = mvwaddch(win, y, x, ch);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+smvwdelch(WINDOW *win, int y, int x)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = mvwdelch(win, y, x);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+smvwaddstr(WINDOW *win, int y, int x, const char *str)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = mvwaddstr(win, y, x, str);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int 
+smvwprintw(WINDOW *win, int y, int x, const char *fmt, ...)
+{
+	char buf[999];
+	va_list args;
+	va_start(args, fmt);
+	vsnprintf(buf, 999, fmt, args);
+	va_end(args);
+
+	return smvwaddstr(win, y, x, buf);
+}
+
+int
+swattron(WINDOW *win, int attrs)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = wattron(win, attrs);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+swattroff(WINDOW *win, int attrs)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = wattroff(win, attrs);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}
+
+int
+swrefresh(WINDOW *win)
+{
+	pthread_mutex_lock(&ncurses_lock);
+	int r = wrefresh(win);
+	pthread_mutex_unlock(&ncurses_lock);
+	return r;
+}

ext/sncurses.h

@@ -0,0 +1,18 @@
+#ifndef SNCURSES
+#define SNCURSES
+#include <ncurses.h>
+
+int sinit_pair(short pair, short f, short b);
+WINDOW *snewwin(int nlines, int ncols, int begin_y, int begin_x);
+int sdelwin(WINDOW *win);
+int sbox(WINDOW *win, chtype verch, chtype horch);
+int swaddch(WINDOW *win, const chtype ch);
+int smvwaddch(WINDOW *win, int y, int x, const chtype ch);
+int smvwdelch(WINDOW *win, int y, int x);
+int smvwaddstr(WINDOW *win, int y, int x, const char *str);
+int smvwprintw(WINDOW *win, int y, int x, const char *fmt, ...);
+int swattron(WINDOW *win, int attrs);
+int swattroff(WINDOW *win, int attrs);
+int swrefresh(WINDOW *win);
+
+#endif

ext/sysext.c

@@ -28,7 +28,7 @@ ext_kill(pid_t pid, int sig)
 		fscanf(f, "%d", &child_pid);
 		fclose(f);
 		kill(pid, sig);
-		pid = child_pid;
+		pid = pid == child_pid ? 0 : child_pid;
 	}
 }
 

ext/thr.c

@@ -10,6 +10,8 @@
 pthread_t load_thr;
 pthread_t display_thr;
 pthread_t preview_thr;
+pthread_cond_t run_preview = PTHREAD_COND_INITIALIZER;
+pthread_mutex_t preview_lock = PTHREAD_MUTEX_INITIALIZER;
 pid_t preview_pid = 0;
 bool items_loading = false;
 
@@ -30,17 +32,23 @@ stop_load()
 }
 
 void
-start_preview(void *load_preview)
+init_preview(void *load_preview)
 {
 	pthread_create(&preview_thr, NULL, load_preview, NULL);
 }
 
 void
-stop_preview()
+queue_preview()
+{
+	pthread_mutex_lock(&preview_lock);
+	pthread_cond_signal(&run_preview);
+	pthread_mutex_unlock(&preview_lock);
+}
+
+void
+cancel_preview()
 {
 	if (preview_pid) {
-		ext_kill(preview_pid, SIGTERM);
-	} if (preview_thr) {
-		pthread_join(preview_thr, NULL);
+		ext_kill(preview_pid, SIGKILL);
 	}
 }

ext/thr.h

@@ -3,7 +3,8 @@
 
 void start_load(void *load_items, void *display_load);
 void stop_load();
-void start_preview(void *load_preview);
-void stop_preview();
+void init_preview(void *load_preview);
+void queue_preview();
+void cancel_preview();
 
 #endif