#include "jemalloc/internal/jemalloc_preamble.h"

#include "jemalloc/internal/jemalloc_internal_includes.h"

#include "jemalloc/internal/log.h"

char log_var_names[JEMALLOC_LOG_VAR_BUFSIZE];

atomic_b_t log_init_done = ATOMIC_INIT(false);

/*

 * Returns true if we were able to pick out a segment.  Fills in r_segment_end

 * with a pointer to the first character after the end of the string.

 */

static const char *

log_var_extract_segment(const char* segment_begin) {

	const char *end;

	for (end = segment_begin; *end != '\0' && *end != '|'; end++) {

	}

	return end;

}

static bool

log_var_matches_segment(const char *segment_begin, const char *segment_end,

    const char *log_var_begin, const char *log_var_end) {

	assert(segment_begin <= segment_end);

	assert(log_var_begin < log_var_end);

	ptrdiff_t segment_len = segment_end - segment_begin;

	ptrdiff_t log_var_len = log_var_end - log_var_begin;

	/* The special '.' segment matches everything. */

	if (segment_len == 1 && *segment_begin == '.') {

		return true;

	}

        if (segment_len == log_var_len) {

		return strncmp(segment_begin, log_var_begin, segment_len) == 0;

	} else if (segment_len < log_var_len) {

		return strncmp(segment_begin, log_var_begin, segment_len) == 0

		    && log_var_begin[segment_len] == '.';

        } else {

		return false;

	}

}

unsigned

log_var_update_state(log_var_t *log_var) {

	const char *log_var_begin = log_var->name;

	const char *log_var_end = log_var->name + strlen(log_var->name);

	/* Pointer to one before the beginning of the current segment. */

	const char *segment_begin = log_var_names;

	/*

	 * If log_init done is false, we haven't parsed the malloc conf yet.  To

	 * avoid log-spew, we default to not displaying anything.

	 */

	if (!atomic_load_b(&log_init_done, ATOMIC_ACQUIRE)) {

		return LOG_INITIALIZED_NOT_ENABLED;

	}

	while (true) {

		const char *segment_end = log_var_extract_segment(

		    segment_begin);

		assert(segment_end < log_var_names + JEMALLOC_LOG_VAR_BUFSIZE);

		if (log_var_matches_segment(segment_begin, segment_end,

		    log_var_begin, log_var_end)) {

			atomic_store_u(&log_var->state, LOG_ENABLED,

			    ATOMIC_RELAXED);

			return LOG_ENABLED;

		}

		if (*segment_end == '\0') {

			/* Hit the end of the segment string with no match. */

			atomic_store_u(&log_var->state,

			    LOG_INITIALIZED_NOT_ENABLED, ATOMIC_RELAXED);

			return LOG_INITIALIZED_NOT_ENABLED;

		}

		/* Otherwise, skip the delimiter and continue. */

		segment_begin = segment_end + 1;

	}

}