/* See LICENSE file for copyright and license details. */
#include "common.h"


static char *
spawn_read(struct libgeome_context *ctx, const char *path, const char *const *argv, size_t limit, unsigned int alarm_seconds)
{
	struct spawn_join_info info;
	char *ret = NULL, *new;
	size_t size = 0;
	size_t len = 0;
	ssize_t r;
	int fd, status;

	if (libgeome_util_spawn_async_read(ctx, path, argv, alarm_seconds, &info, &fd))
		return NULL;

	for (;;) {
		if (len == size) {
			size += 512U;
			new = realloc(ret, size);
			if (!new) {
				ctx->print_error(ctx, "realloc: %s\n", strerror(errno));
				goto read_fail;
			}
			ret = new;
		}
		r = read(fd, &ret[len], size - len);
		if (r <= 0) {
			if (!r)
				break;
			if (errno == EINTR)
				continue;
			ctx->print_error(ctx, "read <pipe>: %s\n", strerror(errno));
		read_fail:
			close(fd);
			free(ret);
			ret = NULL;
			libgeome_util_spawn_async_kill(ctx, &info, SIGKILL);
			break;
		}
		len += (size_t)r;
		if (len >= limit)
			break;
	}

	if (len) {
		if (len == size)
			len--;
		ret[len] = '\0';
	} else {
		free(ret);
		ret = NULL;
	}

	if (libgeome_util_spawn_async_join(ctx, &info, &status) || status != 0) {
		free(ret);
		ret = NULL;
	}
	return ret;
}


int
libgeome_get_from_command(struct libgeome_context *ctx, struct libgeome_data *out, size_t limit,
                          unsigned int alarm_secs, const char *path, const char *const *argv)
{
	struct location location;
	char *text;

	text = spawn_read(ctx, path, argv, limit ? limit : 2048U, alarm_secs);
	if (!text)
		return -1;
	out->requested_data &= libgeome_util_parse_output(text, &location);
	free(text);

	if (out->requested_data & LIBGEOME_DATUM_LATITUDE) {
		if (!isfinite(location.latitude) || location.latitude < -90 || location.latitude > 90) {
			ctx->print_debug(ctx, "invalid latitude retrieved: %g\n", location.latitude);
			out->requested_data ^= LIBGEOME_DATUM_LATITUDE;
		} else {
			out->latitude = location.latitude;
		}
	}

	if (out->requested_data & LIBGEOME_DATUM_LONGITUDE) {
		if (!isfinite(location.longitude) || location.longitude < -180 || location.longitude > 180) {
			ctx->print_debug(ctx, "invalid longitude retrieved: %g\n", location.longitude);
			out->requested_data ^= LIBGEOME_DATUM_LONGITUDE;
		} else {
			out->longitude = location.longitude;
		}
	}

	return 0;
}