1 files changed, 81 insertions, 0 deletions
diff --git a/pkgs/misc/cups/drivers/canon/preload.c b/pkgs/misc/cups/drivers/canon/preload.c
new file mode 100644
index 000000000000..f3a30063a6e3
--- /dev/null
+++ b/pkgs/misc/cups/drivers/canon/preload.c
@@ -0,0 +1,81 @@
+/*
+ * LD_PRELOAD trick to make c3pldrv handle the absolute path to /usr/{bin,lib,share)}.
+ * As c3pldrv is a 32 bit executable, /lib will be rewritten to /lib32.
+ *
+ * Usage:
+ *   gcc -shared -fPIC -DOUT="$out" preload.c -o preload.so -ldl
+ *   LD_PRELOAD=$PWD/preload.so ./c3pldrv
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <dlfcn.h>
+#include <limits.h>
+
+#ifndef OUT
+#error Missing OUT define - path to the installation directory.
+#endif
+
+typedef void *(*dlopen_func_t)(const char *filename, int flag);
+typedef int (*open_func_t)(const char *pathname, int flags, ...);
+typedef int (*execv_func_t)(const char *path, char *const argv[]);
+
+
+void *dlopen(const char *filename, int flag)
+{
+	dlopen_func_t orig_dlopen;
+	const char *new_filename;
+	char buffer[PATH_MAX];
+
+	orig_dlopen = (dlopen_func_t)dlsym(RTLD_NEXT, "dlopen");
+
+	new_filename = filename;
+	if (strncmp("/usr/lib", filename, 8) == 0) {
+		snprintf(buffer, PATH_MAX, OUT "/lib32%s", filename+8);
+		buffer[PATH_MAX-1] = '\0';
+		new_filename = buffer;
+	}
+	
+	return orig_dlopen(new_filename, flag);
+}
+
+int open(const char *pathname, int flags, ...)
+{
+	open_func_t orig_open;
+	const char *new_pathname;
+	char buffer[PATH_MAX];
+
+	orig_open = (open_func_t)dlsym(RTLD_NEXT, "open");
+
+	new_pathname = pathname;
+	if (strncmp("/usr/share", pathname, 10) == 0) {
+		snprintf(buffer, PATH_MAX, OUT "%s", pathname+4);
+		buffer[PATH_MAX-1] = '\0';
+		new_pathname = buffer;
+	}
+	
+	return orig_open(new_pathname, flags);
+}
+
+int execv(const char *path, char *const argv[])
+{
+	execv_func_t orig_execv;
+	const char *new_path;
+	char buffer[PATH_MAX];
+
+	orig_execv = (execv_func_t)dlsym(RTLD_NEXT, "execv");
+
+	new_path = path;
+	if (strncmp("/usr/bin", path, 8) == 0) {
+		snprintf(buffer, PATH_MAX, OUT "%s", path+4);
+		buffer[PATH_MAX-1] = '\0';
+		new_path = buffer;
+	}
+	
+	return orig_execv(new_path, argv);
+}
+