8 files changed, 61 insertions, 40 deletions

diff --git a/.clang-format b/.clang-format
index 1d84013..6e49d83 100644
--- a/.clang-format
+++ b/.clang-format
@@ -8,3 +8,4 @@ IndentWidth: 4
 PointerBindsToType: false
 ColumnLimit: 0
 SpaceBeforeParens: ControlStatements
+SortIncludes: false
diff --git a/.travis.yml b/.travis.yml
index 15ad1e4..6e929e6 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,11 +7,7 @@ language: c
 compiler:
   - gcc
   - clang
-addons:
-  apt:
-    packages:
-    - clang-format-3.5
 script:
-  - clang-format-3.5 -i *.[ch] && git diff --exit-code || (echo 'Code was not formatted using clang-format!'; false)
   - docker build --pull --no-cache --rm -t=i3lock -f travis/Dockerfile .
+  - docker run -e CC=$CC -v $PWD:/usr/src:rw i3lock /bin/sh -c 'clang-format-9 -i *.[ch] && git diff --exit-code || (echo "Code was not formatted using clang-format!"; false)'
   - docker run -e CC=$CC -v $PWD:/usr/src:rw i3lock /bin/sh -c 'autoreconf -fi && mkdir -p build && cd build && (../configure || (cat config.log; false)) && make -j V=1 CFLAGS="-Wformat -Wformat-security -Wextra -Wno-unused-parameter -Werror"'
diff --git a/configure.ac b/configure.ac
index 79f23a9..699e5a6 100644
--- a/configure.ac
+++ b/configure.ac
@@ -66,6 +66,7 @@ AC_FUNC_FORK
 AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK
 AC_FUNC_STRNLEN
 AC_CHECK_FUNCS([atexit dup2 ftruncate getcwd gettimeofday localtime_r memchr memset mkdir rmdir setlocale socket strcasecmp strchr strdup strerror strncasecmp strndup strrchr strspn strstr strtol strtoul], , [AC_MSG_FAILURE([cannot find the $ac_func function, which i3lock requires])])
+AC_CHECK_FUNCS([explicit_bzero])
 
 # Checks for libraries.
 
diff --git a/i3lock.c b/i3lock.c
index 4ef0f73..f7c5bdc 100644
--- a/i3lock.c
+++ b/i3lock.c
@@ -46,7 +46,6 @@
 #include <security/pam_appl.h>
 #endif
 #include <getopt.h>
-#include <string.h>
 #include <ev.h>
 #include <sys/mman.h>
 #include <xkbcommon/xkbcommon.h>
@@ -54,7 +53,7 @@
 #include <xkbcommon/xkbcommon-x11.h>
 #include <cairo.h>
 #include <cairo/cairo-xcb.h>
-#ifdef __OpenBSD__
+#ifdef HAVE_EXPLICIT_BZERO
 #include <strings.h> /* explicit_bzero(3) */
 #endif
 #include <xcb/xcb_aux.h>
@@ -153,7 +152,7 @@ bool skip_repeated_empty_password = false;
  * Decrements i to point to the previous unicode glyph
  *
  */
-void u8_dec(char *s, int *i) {
+static void u8_dec(char *s, int *i) {
     (void)(isutf(s[--(*i)]) || isutf(s[--(*i)]) || isutf(s[--(*i)]) || --(*i));
 }
 
@@ -223,7 +222,7 @@ static bool load_compose_table(const char *locale) {
  *
  */
 static void clear_password_memory(void) {
-#ifdef __OpenBSD__
+#ifdef HAVE_EXPLICIT_BZERO
     /* Use explicit_bzero(3) which was explicitly designed not to be
      * optimized out by the compiler. */
     explicit_bzero(password, strlen(password));
@@ -664,7 +663,7 @@ static void process_xkb_event(xcb_generic_event_t *gevent) {
  * and also redraw the image, if any.
  *
  */
-void handle_screen_resize(void) {
+static void handle_screen_resize(void) {
     xcb_get_geometry_cookie_t geomc;
     xcb_get_geometry_reply_t *geom;
     geomc = xcb_get_geometry(conn, screen->root);
@@ -1119,6 +1118,8 @@ int main(int argc, char *argv[]) {
         err(EXIT_FAILURE, "getpwuid() failed");
     if ((username = pw->pw_name) == NULL)
         errx(EXIT_FAILURE, "pw->pw_name is NULL.");
+    if (getenv("WAYLAND_DISPLAY") != NULL)
+        errx(EXIT_FAILURE, "i3lock is a program for X11 and does not work on Wayland. Try https://github.com/swaywm/swaylock instead");
 
 #ifdef EXTRAS
     char *optstring = "hvnbDdELc:B:G:F:J:O:R:r:S:T:W:X:x:Y:y:Z:p:ui:teI:f";
@@ -1497,7 +1498,8 @@ int main(int argc, char *argv[]) {
     free(image_raw_format);
 
     /* Pixmap on which the image is rendered to (if any) */
-    xcb_pixmap_t bg_pixmap = draw_image(last_resolution);
+    xcb_pixmap_t bg_pixmap = create_bg_pixmap(conn, screen, last_resolution, color);
+    draw_image(bg_pixmap, last_resolution);
 
     xcb_window_t stolen_focus = find_focused_window(conn, screen->root);
 
diff --git a/i3lock.h b/i3lock.h
index 57190e5..6cf7694 100644
--- a/i3lock.h
+++ b/i3lock.h
@@ -5,10 +5,11 @@
  * This is important because xautolock (for example) closes stdout/stderr by
  * default, so just printing something to stdout will lead to the data ending
  * up on the X11 socket (!). */
-#define DEBUG(fmt, ...)                                   \
-    do {                                                  \
-        if (debug_mode)                                   \
-            printf("[i3lock-debug] " fmt, ##__VA_ARGS__); \
+#define DEBUG(fmt, ...)                                            \
+    do {                                                           \
+        if (debug_mode) {                                          \
+            fprintf(stderr, "[i3lock-extended-debug] " fmt, ##__VA_ARGS__); \
+        }                                                          \
     } while (0)
 
 #endif
diff --git a/travis/Dockerfile b/travis/Dockerfile
index 5381276..cc2dd7d 100644
--- a/travis/Dockerfile
+++ b/travis/Dockerfile
@@ -11,7 +11,7 @@ RUN echo 'APT::Acquire::Retries "5";' > /etc/apt/apt.conf.d/80retry
 # (3608 kB/s)). Hence, let’s stick with httpredir.debian.org (default) for now.
 
 # Install mk-build-deps (for installing the i3 build dependencies),
-# clang and clang-format-3.8 (for checking formatting and building with clang),
+# clang and clang-format-9 (for checking formatting and building with clang),
 # lintian (for checking spelling errors),
 # test suite dependencies (for running tests)
 RUN apt-get update && \
@@ -19,7 +19,7 @@ RUN apt-get update && \
     build-essential clang git autoconf automake libxcb-randr0-dev pkg-config libpam0g-dev \
     libcairo2-dev libxcb1-dev libxcb-dpms0-dev libxcb-image0-dev libxcb-util0-dev \
     libxcb-xrm-dev libev-dev libxcb-xinerama0-dev libxcb-xkb-dev libxkbcommon-dev \
-    libxkbcommon-x11-dev && \
+    libxkbcommon-x11-dev clang-format-9 && \
     rm -rf /var/lib/apt/lists/*
 
 WORKDIR /usr/src
diff --git a/unlock_indicator.c b/unlock_indicator.c
index 3d98a5f..73320cb 100644
--- a/unlock_indicator.c
+++ b/unlock_indicator.c
@@ -50,9 +50,9 @@
 #define BUTTON_CENTER (BUTTON_RADIUS + 5)
 #define BUTTON_DIAMETER (2 * BUTTON_SPACE)
 
-/******************************************************************************
+/*******************************************************************************
  * Variables defined in i3lock.c.
- *****************************************************************************/
+ ******************************************************************************/
 
 extern bool debug_mode;
 
@@ -100,16 +100,16 @@ extern bool show_failed_attempts;
 /* Number of failed unlock attempts. */
 extern int failed_attempts;
 
-/******************************************************************************
+/*******************************************************************************
  * Variables defined in xcb.c.
- *****************************************************************************/
+ ******************************************************************************/
 
 /* The root screen, to determine the DPI. */
 extern xcb_screen_t *screen;
 
-/******************************************************************************
+/*******************************************************************************
  * Local variables.
- *****************************************************************************/
+ ******************************************************************************/
 
 /* Cache the screen’s visual, necessary for creating a Cairo context. */
 static xcb_visualtype_t *vistype;
@@ -124,8 +124,7 @@ auth_state_t auth_state;
  * resolution and returns it.
  *
  */
-xcb_pixmap_t draw_image(uint32_t *resolution) {
-    xcb_pixmap_t bg_pixmap = XCB_NONE;
+void draw_image(xcb_pixmap_t bg_pixmap, uint32_t *resolution) {
     const double scaling_factor = get_dpi_value() / 96.0;
     int button_diameter_physical = ceil(scaling_factor * BUTTON_DIAMETER);
     DEBUG("scaling_factor is %.f, physical diameter is %d px\n",
@@ -133,7 +132,7 @@ xcb_pixmap_t draw_image(uint32_t *resolution) {
 
     if (!vistype)
         vistype = get_root_visual_type(screen);
-    bg_pixmap = create_bg_pixmap(conn, screen, resolution, color);
+
     /* Initialize cairo: Create one in-memory surface to render the unlock
      * indicator on, create one XCB surface to actually draw (one or more,
      * depending on the amount of screens) unlock indicators on. */
@@ -143,6 +142,19 @@ xcb_pixmap_t draw_image(uint32_t *resolution) {
     cairo_surface_t *xcb_output = cairo_xcb_surface_create(conn, bg_pixmap, vistype, resolution[0], resolution[1]);
     cairo_t *xcb_ctx = cairo_create(xcb_output);
 
+    /* After the first iteration, the pixmap will still contain the previous
+     * contents. Explicitly clear the entire pixmap with the background color
+     * first to get back into a defined state: */
+    char strgroups[3][3] = {{color[0], color[1], '\0'},
+                            {color[2], color[3], '\0'},
+                            {color[4], color[5], '\0'}};
+    uint32_t rgb16[3] = {(strtol(strgroups[0], NULL, 16)),
+                         (strtol(strgroups[1], NULL, 16)),
+                         (strtol(strgroups[2], NULL, 16))};
+    cairo_set_source_rgb(xcb_ctx, rgb16[0] / 255.0, rgb16[1] / 255.0, rgb16[2] / 255.0);
+    cairo_rectangle(xcb_ctx, 0, 0, resolution[0], resolution[1]);
+    cairo_fill(xcb_ctx);
+
     if (img) {
         if (!tile) {
             cairo_set_source_surface(xcb_ctx, img, 0, 0);
@@ -157,16 +169,6 @@ xcb_pixmap_t draw_image(uint32_t *resolution) {
             cairo_fill(xcb_ctx);
             cairo_pattern_destroy(pattern);
         }
-    } else {
-        char strgroups[3][3] = {{color[0], color[1], '\0'},
-                                {color[2], color[3], '\0'},
-                                {color[4], color[5], '\0'}};
-        uint32_t rgb16[3] = {(strtol(strgroups[0], NULL, 16)),
-                             (strtol(strgroups[1], NULL, 16)),
-                             (strtol(strgroups[2], NULL, 16))};
-        cairo_set_source_rgb(xcb_ctx, rgb16[0] / 255.0, rgb16[1] / 255.0, rgb16[2] / 255.0);
-        cairo_rectangle(xcb_ctx, 0, 0, resolution[0], resolution[1]);
-        cairo_fill(xcb_ctx);
     }
 
     if (unlock_indicator &&
@@ -394,7 +396,18 @@ xcb_pixmap_t draw_image(uint32_t *resolution) {
     cairo_surface_destroy(output);
     cairo_destroy(ctx);
     cairo_destroy(xcb_ctx);
-    return bg_pixmap;
+}
+
+static xcb_pixmap_t bg_pixmap = XCB_NONE;
+
+/*
+ * Releases the current background pixmap so that the next redraw_screen() call
+ * will allocate a new one with the updated resolution.
+ *
+ */
+void free_bg_pixmap(void) {
+    xcb_free_pixmap(conn, bg_pixmap);
+    bg_pixmap = XCB_NONE;
 }
 
 /*
@@ -403,12 +416,16 @@ xcb_pixmap_t draw_image(uint32_t *resolution) {
  */
 void redraw_screen(void) {
     DEBUG("redraw_screen(unlock_state = %d, auth_state = %d)\n", unlock_state, auth_state);
-    xcb_pixmap_t bg_pixmap = draw_image(last_resolution);
+    if (bg_pixmap == XCB_NONE) {
+        DEBUG("allocating pixmap for %d x %d px\n", last_resolution[0], last_resolution[1]);
+        bg_pixmap = create_bg_pixmap(conn, screen, last_resolution, color);
+    }
+
+    draw_image(bg_pixmap, last_resolution);
     xcb_change_window_attributes(conn, win, XCB_CW_BACK_PIXMAP, (uint32_t[1]){bg_pixmap});
     /* XXX: Possible optimization: Only update the area in the middle of the
      * screen instead of the whole screen. */
     xcb_clear_area(conn, 0, win, 0, 0, last_resolution[0], last_resolution[1]);
-    xcb_free_pixmap(conn, bg_pixmap);
     xcb_flush(conn);
 }
 
diff --git a/unlock_indicator.h b/unlock_indicator.h
index 93c1de8..581d028 100644
--- a/unlock_indicator.h
+++ b/unlock_indicator.h
@@ -1,6 +1,8 @@
 #ifndef _UNLOCK_INDICATOR_H
 #define _UNLOCK_INDICATOR_H
 
+#include <xcb/xcb.h>
+
 typedef enum {
     STATE_STARTED = 0,           /* default state */
     STATE_KEY_PRESSED = 1,       /* key was pressed, show unlock indicator */
@@ -19,7 +21,8 @@ typedef enum {
     STATE_I3LOCK_LOCK_FAILED = 4, /* i3lock failed to load */
 } auth_state_t;
 
-xcb_pixmap_t draw_image(uint32_t* resolution);
+void free_bg_pixmap(void);
+void draw_image(xcb_pixmap_t bg_pixmap, uint32_t* resolution);
 void redraw_screen(void);
 void clear_indicator(void);