Provide a way to test the configuration

[jvoisin]

Currently, the only way to verify that a configuration file is valid is to restart PHP: this is inconvenient.

We should provide a standalone binary to perform configuration validation. Since we're doing manual parsing instead of using shlex/yacc/bison/… as the rest of the zoo, we should re-use the code, instead of writing a linter in an other language, since it'll be tedious to keep them in since.

[jvoisin]

The obvious solution would be something like this I guess:

#include <stdio.h>
#include <stdlib.h>
#include <dlfcn.h>

int main(int argc, char** argv) {
	char* error;
	int (*sp_parse_config)(const char*);

	if (argc <= 2) {
		printf("Usage: %s file ...", argv[0]);
		return -1;
	}

	void* handle = dlopen("./.libs/snuffleupagus.so", RTLD_LAZY | RTLD_DEEPBIND);
	if (!handle) {
		fprintf(stderr, "%s\n", dlerror());
		return -1;
	}
	dlerror(); 

	sp_parse_config = (int (*)(const char*)) dlsym(handle, "sp_parse_config");
	error = dlerror();
	if (error != NULL) {
		fprintf(stderr, "%s\n", error);
		return -1;
	}

	for(int i=0; i != argc; i++) {
		int ret = sp_parse_config(argv[i]);
		if (ret != 0) {
			return -1;
		}
	}
	dlclose(handle);
	return 0;
}

But PHP's modules are a bit weird, with a lot of moving pieces between the .so and the main PHP binary, so it's not working well™

[bef]

My current work-in-progress solution is to export the configuration in PHP serialized format for use with separate tools. The export part is already implemented. As for the tools, I think about adding unit tests for ini-checks and disabled_functions that can be embedded into the config file as comments and parsed separately by the external config checker tool.