Consolidate all convert_* functions into libi3.

Some minor fixes along the way as well. Very minor stuff, unlikely
to ever be visible to the user.

src/sighandler.c

@@ -51,7 +51,7 @@ static int sig_draw_window(xcb_window_t win, int width, int height, int font_hei
 
     for (int i = 0; i < sizeof(crash_text) / sizeof(char*); i++) {
         int text_len = strlen(crash_text[i]);
-        char *full_text = convert_utf8_to_ucs2(crash_text[i], &text_len);
+        xcb_char2b_t *full_text = convert_utf8_to_ucs2(crash_text[i], &text_len);
         xcb_image_text_16(conn, text_len, pixmap, pixmap_gc, 8 /* X */,
                           3 + (i + 1) * font_height /* Y = baseline of font */,
                           (xcb_char2b_t*)full_text);
@@ -151,7 +151,7 @@ void handle_signal(int sig, siginfo_t *info, void *data) {
 
     /* calculate width for longest text */
     int text_len = strlen(crash_text[crash_text_longest]);
-    char *longest_text = convert_utf8_to_ucs2(crash_text[crash_text_longest], &text_len);
+    xcb_char2b_t *longest_text = convert_utf8_to_ucs2(crash_text[crash_text_longest], &text_len);
     int font_width = predict_text_width(longest_text, text_len);
     int width = font_width + 20;
 

src/util.c

@@ -12,7 +12,6 @@
 
 #include <sys/wait.h>
 #include <stdarg.h>
-#include <iconv.h>
 #if defined(__OpenBSD__)
 #include <sys/cdefs.h>
 #endif
@@ -24,8 +23,6 @@
 #define SN_API_NOT_YET_FROZEN 1
 #include <libsn/sn-launcher.h>
 
-static iconv_t conversion_descriptor = 0;
-
 int min(int a, int b) {
     return (a < b ? a : b);
 }
@@ -120,51 +117,6 @@ void check_error(xcb_connection_t *conn, xcb_void_cookie_t cookie, char *err_mes
     }
 }
 
-/*
- * Converts the given string to UCS-2 big endian for use with
- * xcb_image_text_16(). The amount of real glyphs is stored in real_strlen,
- * a buffer containing the UCS-2 encoded string (16 bit per glyph) is
- * returned. It has to be freed when done.
- *
- */
-char *convert_utf8_to_ucs2(char *input, int *real_strlen) {
-    size_t input_size = strlen(input) + 1;
-    /* UCS-2 consumes exactly two bytes for each glyph */
-    int buffer_size = input_size * 2;
-
-    char *buffer = smalloc(buffer_size);
-    size_t output_size = buffer_size;
-    /* We need to use an additional pointer, because iconv() modifies it */
-    char *output = buffer;
-
-    /* We convert the input into UCS-2 big endian */
-    if (conversion_descriptor == 0) {
-        conversion_descriptor = iconv_open("UCS-2BE", "UTF-8");
-        if (conversion_descriptor == 0) {
-            fprintf(stderr, "error opening the conversion context\n");
-            exit(1);
-        }
-    }
-
-    /* Get the conversion descriptor back to original state */
-    iconv(conversion_descriptor, NULL, NULL, NULL, NULL);
-
-    /* Convert our text */
-    int rc = iconv(conversion_descriptor, (void*)&input, &input_size, &output, &output_size);
-    if (rc == (size_t)-1) {
-        perror("Converting to UCS-2 failed");
-        FREE(buffer);
-        if (real_strlen != NULL)
-            *real_strlen = 0;
-        return NULL;
-    }
-
-    if (real_strlen != NULL)
-        *real_strlen = ((buffer_size - output_size) / 2) - 1;
-
-    return buffer;
-}
-
 /*
  * This function resolves ~ in pathnames.
  * It may resolve wildcards in the first part of the path, but if no match

src/window.c

@@ -69,7 +69,7 @@ void window_update_name(i3Window *win, xcb_get_property_reply_t *prop, bool befo
     }
     /* Convert it to UCS-2 here for not having to convert it later every time we want to pass it to X */
     int len;
-    char *ucs2_name = convert_utf8_to_ucs2(new_name, &len);
+    xcb_char2b_t *ucs2_name = convert_utf8_to_ucs2(new_name, &len);
     if (ucs2_name == NULL) {
         LOG("Could not convert _NET_WM_NAME to UCS-2, ignoring new hint\n");
         FREE(new_name);
@@ -79,7 +79,7 @@ void window_update_name(i3Window *win, xcb_get_property_reply_t *prop, bool befo
     FREE(win->name_x);
     FREE(win->name_json);
     win->name_json = new_name;
-    win->name_x = ucs2_name;
+    win->name_x = (char*)ucs2_name;
     win->name_len = len;
     win->name_x_changed = true;
     LOG("_NET_WM_NAME changed to \"%s\"\n", win->name_json);

src/xcb.c

@@ -135,13 +135,13 @@ void xcb_raise_window(xcb_connection_t *conn, xcb_window_t window) {
  * length (amount of glyphs) using the given font.
  *
  */
-int predict_text_width(char *text, int length) {
+int predict_text_width(const xcb_char2b_t *text, int length) {
     xcb_query_text_extents_cookie_t cookie;
     xcb_query_text_extents_reply_t *reply;
     xcb_generic_error_t *error;
     int width;
 
-    cookie = xcb_query_text_extents(conn, config.font.id, length, (xcb_char2b_t*)text);
+    cookie = xcb_query_text_extents(conn, config.font.id, length, text);
     if ((reply = xcb_query_text_extents_reply(conn, cookie, &error)) == NULL) {
         ELOG("Could not get text extents (X error code %d)\n",
              error->error_code);