uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/tools/X11/xkbvalidate/xkbvalidate.c

@@ -0,0 +1,150 @@
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <xkbcommon/xkbcommon.h>
+
+static char **log_buffer = NULL;
+static int log_buffer_size = 0;
+static bool log_alloc_success = true;
+
+static void add_log(struct xkb_context *ctx, enum xkb_log_level level,
+                    const char *fmt, va_list args)
+{
+    size_t buflen;
+    va_list tmpargs;
+
+    log_buffer_size++;
+
+    if (log_buffer == NULL)
+        log_buffer = malloc(sizeof(char *));
+    else
+        log_buffer = realloc(log_buffer, sizeof(char *) * log_buffer_size);
+
+    if (log_buffer == NULL) {
+        perror("buffer alloc");
+        log_alloc_success = false;
+        log_buffer_size--;
+        return;
+    }
+
+    /* Unfortunately, vasprintf() is a GNU extension and thus not very
+     * portable, so let's first get the required buffer size using a dummy
+     * vsnprintf and afterwards allocate the returned amount of bytes.
+     *
+     * We also need to make a copy of the args, because the value of the args
+     * will be indeterminate after the return.
+     */
+    va_copy(tmpargs, args);
+    buflen = vsnprintf(NULL, 0, fmt, tmpargs);
+    va_end(tmpargs);
+
+    log_buffer[log_buffer_size - 1] = malloc(++buflen);
+
+    if (vsnprintf(log_buffer[log_buffer_size - 1], buflen, fmt, args) == -1) {
+        perror("log line alloc");
+        log_alloc_success = false;
+    }
+    va_end(args);
+}
+
+static void print_logs(void)
+{
+    for (int i = 0; i < log_buffer_size; ++i)
+        fprintf(stderr, "    %s", log_buffer[i]);
+}
+
+static void free_logs(void)
+{
+    if (log_buffer == NULL)
+        return;
+    for (int i = 0; i < log_buffer_size; ++i)
+        free(log_buffer[i]);
+    free(log_buffer);
+    log_buffer = NULL;
+    log_buffer_size = 0;
+}
+
+static bool try_keymap(struct xkb_context *ctx, struct xkb_rule_names *rdef)
+{
+    struct xkb_keymap *keymap;
+    bool result = true;
+
+    if ((keymap = xkb_keymap_new_from_names(ctx, rdef, 0)) == NULL)
+        result = false;
+    else
+        xkb_keymap_unref(keymap);
+
+    return result;
+}
+
+static void print_error(const char *name, const char *value,
+                        const char *nixos_option)
+{
+    fprintf(stderr, "\nThe value `%s' for keyboard %s is invalid.\n\n"
+                    "Please check the definition in `services.xserver.%s'.\n",
+            value, name, nixos_option);
+    fputs("\nDetailed XKB compiler errors:\n\n", stderr);
+    print_logs();
+    putc('\n', stderr);
+}
+
+#define TRY_KEYMAP(name, value, nixos_option) \
+    *rdef = (struct xkb_rule_names) {0}; \
+    free_logs(); \
+    rdef->name = value; \
+    result = try_keymap(ctx, rdef); \
+    if (!log_alloc_success) \
+        goto out; \
+    if (!result) { \
+        print_error(#name, value, nixos_option); \
+        exit_code = EXIT_FAILURE; \
+        goto out; \
+    }
+
+int main(int argc, char **argv)
+{
+    int exit_code = EXIT_SUCCESS;
+    bool result;
+    struct xkb_context *ctx;
+    struct xkb_rule_names *rdef;
+
+    if (argc != 5) {
+        fprintf(stderr, "Usage: %s model layout variant options\n", argv[0]);
+        return EXIT_FAILURE;
+    }
+
+    ctx = xkb_context_new(XKB_CONTEXT_NO_ENVIRONMENT_NAMES);
+    xkb_context_set_log_fn(ctx, add_log);
+
+    rdef = malloc(sizeof(struct xkb_rule_names));
+
+    TRY_KEYMAP(model,   argv[1], "xkbModel");
+    TRY_KEYMAP(layout,  argv[2], "layout");
+    TRY_KEYMAP(variant, argv[3], "xkbVariant");
+    TRY_KEYMAP(options, argv[4], "xkbOptions");
+
+    free_logs();
+    rdef->model = argv[1];
+    rdef->layout = argv[2];
+    rdef->variant = argv[3];
+    rdef->options = argv[4];
+
+    result = try_keymap(ctx, rdef);
+    if (!log_alloc_success)
+        goto out;
+
+    if (!result) {
+        fputs("The XKB keyboard definition failed to compile:\n", stderr);
+        print_logs();
+        exit_code = EXIT_FAILURE;
+    }
+
+out:
+    free_logs();
+    free(rdef);
+    xkb_context_unref(ctx);
+    return exit_code;
+}