X-Git-Url: https://arthur.barton.de/gitweb/?a=blobdiff_plain;f=src%2Fappconfig.c;h=ae92ad0454a16444aeff44443913e6d79c5a5dfa;hb=909e26f825bc1f6f907231761412c885331fec7e;hp=86c229372d8185046685cbc382682f143d9ce345;hpb=f7e35af6cdd5a820833bae3db41f340c175c4565;p=netdata.git

diff --git a/src/appconfig.c b/src/appconfig.c
old mode 100755
new mode 100644
index 86c22937..ae92ad04
--- a/src/appconfig.c
+++ b/src/appconfig.c
@@ -1,19 +1,7 @@
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-#include <pthread.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "avl.h"
 #include "common.h"
-#include "appconfig.h"
-#include "log.h"
 
 #define CONFIG_FILE_LINE_MAX ((CONFIG_MAX_NAME + CONFIG_MAX_VALUE + 1024) * 2)
 
-pthread_rwlock_t config_rwlock = PTHREAD_RWLOCK_INITIALIZER;
-
 // ----------------------------------------------------------------------------
 // definitions
 
@@ -22,464 +10,570 @@ pthread_rwlock_t config_rwlock = PTHREAD_RWLOCK_INITIALIZER;
 #define CONFIG_VALUE_CHANGED 0x04 // has been changed from the loaded value
 #define CONFIG_VALUE_CHECKED 0x08 // has been checked if the value is different from the default
 
-struct config_value {
-	avl avl;				// the index - this has to be first!
-
-	uint32_t hash;			// a simple hash to speed up searching
-							// we first compare hashes, and only if the hashes are equal we do string comparisons
+struct config_option {
+    avl avl;                // the index - this has to be first!
 
-	char *name;
-	char *value;
+    uint8_t flags;
+    uint32_t hash;          // a simple hash to speed up searching
+                            // we first compare hashes, and only if the hashes are equal we do string comparisons
 
-	uint8_t	flags;
+    char *name;
+    char *value;
 
-	struct config_value *next;
+    struct config_option *next; // config->mutex protects just this
 };
 
-struct config {
-	avl avl;
+struct section {
+    avl avl;
 
-	uint32_t hash;			// a simple hash to speed up searching
-							// we first compare hashes, and only if the hashes are equal we do string comparisons
+    uint32_t hash;          // a simple hash to speed up searching
+                            // we first compare hashes, and only if the hashes are equal we do string comparisons
 
-	char *name;
+    char *name;
 
-	struct config_value *values;
-	avl_tree values_index;
+    struct section *next;    // gloabl config_mutex protects just this
 
-	struct config *next;
+    struct config_option *values;
+    avl_tree_lock values_index;
 
-	pthread_rwlock_t rwlock;
-} *config_root = NULL;
+    netdata_mutex_t mutex;  // this locks only the writers, to ensure atomic updates
+                            // readers are protected using the rwlock in avl_tree_lock
+};
 
+static int appconfig_section_compare(void *a, void *b);
 
-// ----------------------------------------------------------------------------
-// config value
+struct config netdata_config = {
+        .sections = NULL,
+        .mutex = NETDATA_MUTEX_INITIALIZER,
+        .index = {
+            { NULL, appconfig_section_compare },
+            AVL_LOCK_INITIALIZER
+        }
+};
 
-static int config_value_iterator(avl *a) { if(a) {}; return 0; }
+struct config stream_config = {
+        .sections = NULL,
+        .mutex = NETDATA_MUTEX_INITIALIZER,
+        .index = {
+                { NULL, appconfig_section_compare },
+                AVL_LOCK_INITIALIZER
+        }
+};
 
-static int config_value_compare(void* a, void* b) {
-	if(((struct config_value *)a)->hash < ((struct config_value *)b)->hash) return -1;
-	else if(((struct config_value *)a)->hash > ((struct config_value *)b)->hash) return 1;
-	else return strcmp(((struct config_value *)a)->name, ((struct config_value *)b)->name);
+// ----------------------------------------------------------------------------
+// locking
+
+static inline void appconfig_wrlock(struct config *root) {
+    netdata_mutex_lock(&root->mutex);
 }
 
-#define config_value_index_add(co, cv) avl_insert(&((co)->values_index), (avl *)(cv))
-#define config_value_index_del(co, cv) avl_remove(&((co)->values_index), (avl *)(cv))
+static inline void appconfig_unlock(struct config *root) {
+    netdata_mutex_unlock(&root->mutex);
+}
 
-static struct config_value *config_value_index_find(struct config *co, const char *name, uint32_t hash) {
-	struct config_value *result = NULL, tmp;
-	tmp.hash = (hash)?hash:simple_hash(name);
-	tmp.name = (char *)name;
+static inline void config_section_wrlock(struct section *co) {
+    netdata_mutex_lock(&co->mutex);
+}
 
-	avl_search(&(co->values_index), (avl *)&tmp, config_value_iterator, (avl **)&result);
-	return result;
+static inline void config_section_unlock(struct section *co) {
+    netdata_mutex_unlock(&co->mutex);
 }
 
+
 // ----------------------------------------------------------------------------
-// config
+// config name-value index
 
-static int config_iterator(avl *a) { if(a) {}; return 0; }
+static int appconfig_option_compare(void *a, void *b) {
+    if(((struct config_option *)a)->hash < ((struct config_option *)b)->hash) return -1;
+    else if(((struct config_option *)a)->hash > ((struct config_option *)b)->hash) return 1;
+    else return strcmp(((struct config_option *)a)->name, ((struct config_option *)b)->name);
+}
+
+#define appconfig_option_index_add(co, cv) (struct config_option *)avl_insert_lock(&((co)->values_index), (avl *)(cv))
+#define appconfig_option_index_del(co, cv) (struct config_option *)avl_remove_lock(&((co)->values_index), (avl *)(cv))
+
+static struct config_option *appconfig_option_index_find(struct section *co, const char *name, uint32_t hash) {
+    struct config_option tmp;
+    tmp.hash = (hash)?hash:simple_hash(name);
+    tmp.name = (char *)name;
 
-static int config_compare(void* a, void* b) {
-	if(((struct config *)a)->hash < ((struct config *)b)->hash) return -1;
-	else if(((struct config *)a)->hash > ((struct config *)b)->hash) return 1;
-	else return strcmp(((struct config *)a)->name, ((struct config *)b)->name);
+    return (struct config_option *)avl_search_lock(&(co->values_index), (avl *) &tmp);
 }
 
-avl_tree config_root_index = {
-		NULL,
-		config_compare,
-#ifdef AVL_LOCK_WITH_MUTEX
-		PTHREAD_MUTEX_INITIALIZER
-#else
-		PTHREAD_RWLOCK_INITIALIZER
-#endif
-};
 
-#define config_index_add(cfg) avl_insert(&config_root_index, (avl *)(cfg))
-#define config_index_del(cfg) avl_remove(&config_root_index, (avl *)(cfg))
+// ----------------------------------------------------------------------------
+// config sections index
 
-static struct config *config_index_find(const char *name, uint32_t hash) {
-	struct config *result = NULL, tmp;
-	tmp.hash = (hash)?hash:simple_hash(name);
-	tmp.name = (char *)name;
+static int appconfig_section_compare(void *a, void *b) {
+    if(((struct section *)a)->hash < ((struct section *)b)->hash) return -1;
+    else if(((struct section *)a)->hash > ((struct section *)b)->hash) return 1;
+    else return strcmp(((struct section *)a)->name, ((struct section *)b)->name);
+}
 
-	avl_search(&config_root_index, (avl *)&tmp, config_iterator, (avl **)&result);
-	return result;
+#define appconfig_index_add(root, cfg) (struct section *)avl_insert_lock(&root->index, (avl *)(cfg))
+#define appconfig_index_del(root, cfg) (struct section *)avl_remove_lock(&root->index, (avl *)(cfg))
+
+static struct section *appconfig_index_find(struct config *root, const char *name, uint32_t hash) {
+    struct section tmp;
+    tmp.hash = (hash)?hash:simple_hash(name);
+    tmp.name = (char *)name;
+
+    return (struct section *)avl_search_lock(&root->index, (avl *) &tmp);
 }
 
-struct config_value *config_value_create(struct config *co, const char *name, const char *value)
-{
-	debug(D_CONFIG, "Creating config entry for name '%s', value '%s', in section '%s'.", name, value, co->name);
 
-	struct config_value *cv = calloc(1, sizeof(struct config_value));
-	if(!cv) fatal("Cannot allocate config_value");
+// ----------------------------------------------------------------------------
+// config section methods
 
-	cv->name = strdup(name);
-	if(!cv->name) fatal("Cannot allocate config.name");
-	cv->hash = simple_hash(cv->name);
+static inline struct section *appconfig_section_find(struct config *root, const char *section) {
+    return appconfig_index_find(root, section, 0);
+}
 
-	cv->value = strdup(value);
-	if(!cv->value) fatal("Cannot allocate config.value");
+static inline struct section *appconfig_section_create(struct config *root, const char *section) {
+    debug(D_CONFIG, "Creating section '%s'.", section);
 
-	config_value_index_add(co, cv);
+    struct section *co = callocz(1, sizeof(struct section));
+    co->name = strdupz(section);
+    co->hash = simple_hash(co->name);
 
-	// no need for string termination, due to calloc()
+    avl_init_lock(&co->values_index, appconfig_option_compare);
 
-	pthread_rwlock_wrlock(&co->rwlock);
+    if(unlikely(appconfig_index_add(root, co) != co))
+        error("INTERNAL ERROR: indexing of section '%s', already exists.", co->name);
 
-	struct config_value *cv2 = co->values;
-	if(cv2) {
-		while (cv2->next) cv2 = cv2->next;
-		cv2->next = cv;
-	}
-	else co->values = cv;
+    appconfig_wrlock(root);
+    struct section *co2 = root->sections;
+    if(co2) {
+        while (co2->next) co2 = co2->next;
+        co2->next = co;
+    }
+    else root->sections = co;
+    appconfig_unlock(root);
+
+    return co;
+}
 
-	pthread_rwlock_unlock(&co->rwlock);
 
-	return cv;
+// ----------------------------------------------------------------------------
+// config name-value methods
+
+static inline struct config_option *appconfig_value_create(struct section *co, const char *name, const char *value) {
+    debug(D_CONFIG, "Creating config entry for name '%s', value '%s', in section '%s'.", name, value, co->name);
+
+    struct config_option *cv = callocz(1, sizeof(struct config_option));
+    cv->name = strdupz(name);
+    cv->hash = simple_hash(cv->name);
+    cv->value = strdupz(value);
+
+    struct config_option *found = appconfig_option_index_add(co, cv);
+    if(found != cv) {
+        error("indexing of config '%s' in section '%s': already exists - using the existing one.", cv->name, co->name);
+        freez(cv->value);
+        freez(cv->name);
+        freez(cv);
+        return found;
+    }
+
+    config_section_wrlock(co);
+    struct config_option *cv2 = co->values;
+    if(cv2) {
+        while (cv2->next) cv2 = cv2->next;
+        cv2->next = cv;
+    }
+    else co->values = cv;
+    config_section_unlock(co);
+
+    return cv;
 }
 
-struct config *config_create(const char *section)
-{
-	debug(D_CONFIG, "Creating section '%s'.", section);
+int appconfig_exists(struct config *root, const char *section, const char *name) {
+    struct config_option *cv;
 
-	struct config *co = calloc(1, sizeof(struct config));
-	if(!co) fatal("Cannot allocate config");
+    debug(D_CONFIG, "request to get config in section '%s', name '%s'", section, name);
 
-	co->name = strdup(section);
-	if(!co->name) fatal("Cannot allocate config.name");
-	co->hash = simple_hash(co->name);
+    struct section *co = appconfig_section_find(root, section);
+    if(!co) return 0;
 
-	pthread_rwlock_init(&co->rwlock, NULL);
-	avl_init(&co->values_index, config_value_compare);
+    cv = appconfig_option_index_find(co, name, 0);
+    if(!cv) return 0;
 
-	config_index_add(co);
+    return 1;
+}
 
-	// no need for string termination, due to calloc()
+int appconfig_move(struct config *root, const char *section_old, const char *name_old, const char *section_new, const char *name_new) {
+    struct config_option *cv_old, *cv_new;
+    int ret = -1;
 
-	pthread_rwlock_wrlock(&config_rwlock);
+    debug(D_CONFIG, "request to rename config in section '%s', old name '%s', to section '%s', new name '%s'", section_old, name_old, section_new, name_new);
 
-	struct config *co2 = config_root;
-	if(co2) {
-		while (co2->next) co2 = co2->next;
-		co2->next = co;
-	}
-	else config_root = co;
+    struct section *co_old = appconfig_section_find(root, section_old);
+    if(!co_old) return ret;
 
-	pthread_rwlock_unlock(&config_rwlock);
+    struct section *co_new = appconfig_section_find(root, section_new);
+    if(!co_new) co_new = appconfig_section_create(root, section_new);
 
-	return co;
-}
+    config_section_wrlock(co_old);
+    config_section_wrlock(co_new);
 
-struct config *config_find_section(const char *section)
-{
-	return config_index_find(section, 0);
-}
+    cv_old = appconfig_option_index_find(co_old, name_old, 0);
+    if(!cv_old) goto cleanup;
 
-int load_config(char *filename, int overwrite_used)
-{
-	int line = 0;
-	struct config *co = NULL;
-
-	char buffer[CONFIG_FILE_LINE_MAX + 1], *s;
-
-	if(!filename) filename = CONFIG_DIR "/" CONFIG_FILENAME;
-	FILE *fp = fopen(filename, "r");
-	if(!fp) {
-		error("Cannot open file '%s'", filename);
-		return 0;
-	}
-
-	while(fgets(buffer, CONFIG_FILE_LINE_MAX, fp) != NULL) {
-		buffer[CONFIG_FILE_LINE_MAX] = '\0';
-		line++;
-
-		s = trim(buffer);
-		if(!s) {
-			debug(D_CONFIG, "Ignoring line %d, it is empty.", line);
-			continue;
-		}
-
-		int len = (int) strlen(s);
-		if(*s == '[' && s[len - 1] == ']') {
-			// new section
-			s[len - 1] = '\0';
-			s++;
-
-			co = config_find_section(s);
-			if(!co) co = config_create(s);
-
-			continue;
-		}
-
-		if(!co) {
-			// line outside a section
-			error("Ignoring line %d ('%s'), it is outsize all sections.", line, s);
-			continue;
-		}
-
-		char *name = s;
-		char *value = strchr(s, '=');
-		if(!value) {
-			error("Ignoring line %d ('%s'), there is no = in it.", line, s);
-			continue;
-		}
-		*value = '\0';
-		value++;
-
-		name = trim(name);
-		value = trim(value);
-
-		if(!name) {
-			error("Ignoring line %d, name is empty.", line);
-			continue;
-		}
-		if(!value) {
-			debug(D_CONFIG, "Ignoring line %d, value is empty.", line);
-			continue;
-		}
-
-		struct config_value *cv = config_value_index_find(co, name, 0);
-
-		if(!cv) cv = config_value_create(co, name, value);
-		else {
-			if(((cv->flags & CONFIG_VALUE_USED) && overwrite_used) || !(cv->flags & CONFIG_VALUE_USED)) {
-				debug(D_CONFIG, "Overwriting '%s/%s'.", line, co->name, cv->name);
-				free(cv->value);
-				cv->value = strdup(value);
-				if(!cv->value) fatal("Cannot allocate config.value");
-			}
-			else
-				debug(D_CONFIG, "Ignoring line %d, '%s/%s' is already present and used.", line, co->name, cv->name);
-		}
-		cv->flags |= CONFIG_VALUE_LOADED;
-	}
-
-	fclose(fp);
-
-	return 1;
+    cv_new = appconfig_option_index_find(co_new, name_new, 0);
+    if(cv_new) goto cleanup;
+
+    if(unlikely(appconfig_option_index_del(co_old, cv_old) != cv_old))
+        error("INTERNAL ERROR: deletion of config '%s' from section '%s', deleted tge wrong config entry.", cv_old->name, co_old->name);
+
+    if(co_old->values == cv_old) {
+        co_old->values = cv_old->next;
+    }
+    else {
+        struct config_option *t;
+        for(t = co_old->values; t && t->next != cv_old ;t = t->next) ;
+        if(!t || t->next != cv_old)
+            error("INTERNAL ERROR: cannot find variable '%s' in section '%s' of the config - but it should be there.", cv_old->name, co_old->name);
+        else
+            t->next = cv_old->next;
+    }
+
+    freez(cv_old->name);
+    cv_old->name = strdupz(name_new);
+    cv_old->hash = simple_hash(cv_old->name);
+
+    cv_new = cv_old;
+    cv_new->next = co_new->values;
+    co_new->values = cv_new;
+
+    if(unlikely(appconfig_option_index_add(co_new, cv_old) != cv_old))
+        error("INTERNAL ERROR: re-indexing of config '%s' in section '%s', already exists.", cv_old->name, co_new->name);
+
+    ret = 0;
+
+cleanup:
+    config_section_unlock(co_new);
+    config_section_unlock(co_old);
+    return ret;
 }
 
-char *config_get(const char *section, const char *name, const char *default_value)
+char *appconfig_get(struct config *root, const char *section, const char *name, const char *default_value)
 {
-	struct config_value *cv;
-
-	debug(D_CONFIG, "request to get config in section '%s', name '%s', default_value '%s'", section, name, default_value);
-
-	struct config *co = config_find_section(section);
-	if(!co) co = config_create(section);
-
-	cv = config_value_index_find(co, name, 0);
-	if(!cv) {
-		cv = config_value_create(co, name, default_value);
-		if(!cv) return NULL;
-	}
-	cv->flags |= CONFIG_VALUE_USED;
-
-	if((cv->flags & CONFIG_VALUE_LOADED) || (cv->flags & CONFIG_VALUE_CHANGED)) {
-		// this is a loaded value from the config file
-		// if it is different that the default, mark it
-		if(!(cv->flags & CONFIG_VALUE_CHECKED)) {
-			if(strcmp(cv->value, default_value) != 0) cv->flags |= CONFIG_VALUE_CHANGED;
-			cv->flags |= CONFIG_VALUE_CHECKED;
-		}
-	}
-
-	return(cv->value);
+    struct config_option *cv;
+
+    debug(D_CONFIG, "request to get config in section '%s', name '%s', default_value '%s'", section, name, default_value);
+
+    struct section *co = appconfig_section_find(root, section);
+    if(!co) co = appconfig_section_create(root, section);
+
+    cv = appconfig_option_index_find(co, name, 0);
+    if(!cv) {
+        cv = appconfig_value_create(co, name, default_value);
+        if(!cv) return NULL;
+    }
+    cv->flags |= CONFIG_VALUE_USED;
+
+    if((cv->flags & CONFIG_VALUE_LOADED) || (cv->flags & CONFIG_VALUE_CHANGED)) {
+        // this is a loaded value from the config file
+        // if it is different that the default, mark it
+        if(!(cv->flags & CONFIG_VALUE_CHECKED)) {
+            if(strcmp(cv->value, default_value) != 0) cv->flags |= CONFIG_VALUE_CHANGED;
+            cv->flags |= CONFIG_VALUE_CHECKED;
+        }
+    }
+
+    return(cv->value);
 }
 
-long long config_get_number(const char *section, const char *name, long long value)
+long long appconfig_get_number(struct config *root, const char *section, const char *name, long long value)
 {
-	char buffer[100], *s;
-	sprintf(buffer, "%lld", value);
+    char buffer[100], *s;
+    sprintf(buffer, "%lld", value);
 
-	s = config_get(section, name, buffer);
-	if(!s) return value;
+    s = appconfig_get(root, section, name, buffer);
+    if(!s) return value;
 
-	return strtoll(s, NULL, 0);
+    return strtoll(s, NULL, 0);
 }
 
-int config_get_boolean(const char *section, const char *name, int value)
+int appconfig_get_boolean(struct config *root, const char *section, const char *name, int value)
 {
-	char *s;
-	if(value) s = "yes";
-	else s = "no";
+    char *s;
+    if(value) s = "yes";
+    else s = "no";
 
-	s = config_get(section, name, s);
-	if(!s) return value;
+    s = appconfig_get(root, section, name, s);
+    if(!s) return value;
 
-	if(!strcmp(s, "yes")) return 1;
-	else return 0;
+    if(!strcmp(s, "yes") || !strcmp(s, "auto") || !strcmp(s, "on demand")) return 1;
+    return 0;
 }
 
-int config_get_boolean_ondemand(const char *section, const char *name, int value)
+int appconfig_get_boolean_ondemand(struct config *root, const char *section, const char *name, int value)
 {
-	char *s;
+    char *s;
 
-	if(value == CONFIG_ONDEMAND_ONDEMAND)
-		s = "on demand";
+    if(value == CONFIG_BOOLEAN_AUTO)
+        s = "auto";
 
-	else if(value == CONFIG_ONDEMAND_NO)
-		s = "no";
+    else if(value == CONFIG_BOOLEAN_NO)
+        s = "no";
 
-	else
-		s = "yes";
+    else
+        s = "yes";
 
-	s = config_get(section, name, s);
-	if(!s) return value;
+    s = appconfig_get(root, section, name, s);
+    if(!s) return value;
 
-	if(!strcmp(s, "yes"))
-		return CONFIG_ONDEMAND_YES;
-	else if(!strcmp(s, "no"))
-		return CONFIG_ONDEMAND_NO;
-	else if(!strcmp(s, "on demand"))
-		return CONFIG_ONDEMAND_ONDEMAND;
+    if(!strcmp(s, "yes"))
+        return CONFIG_BOOLEAN_YES;
+    else if(!strcmp(s, "no"))
+        return CONFIG_BOOLEAN_NO;
+    else if(!strcmp(s, "auto") || !strcmp(s, "on demand"))
+        return CONFIG_BOOLEAN_AUTO;
 
-	return value;
+    return value;
 }
 
-const char *config_set_default(const char *section, const char *name, const char *value)
+const char *appconfig_set_default(struct config *root, const char *section, const char *name, const char *value)
 {
-	struct config_value *cv;
+    struct config_option *cv;
 
-	debug(D_CONFIG, "request to set config in section '%s', name '%s', value '%s'", section, name, value);
+    debug(D_CONFIG, "request to set default config in section '%s', name '%s', value '%s'", section, name, value);
 
-	struct config *co = config_find_section(section);
-	if(!co) return config_set(section, name, value);
+    struct section *co = appconfig_section_find(root, section);
+    if(!co) return appconfig_set(root, section, name, value);
 
-	cv = config_value_index_find(co, name, 0);
-	if(!cv) return config_set(section, name, value);
+    cv = appconfig_option_index_find(co, name, 0);
+    if(!cv) return appconfig_set(root, section, name, value);
 
-	cv->flags |= CONFIG_VALUE_USED;
+    cv->flags |= CONFIG_VALUE_USED;
 
-	if(cv->flags & CONFIG_VALUE_LOADED)
-		return cv->value;
+    if(cv->flags & CONFIG_VALUE_LOADED)
+        return cv->value;
 
-	if(strcmp(cv->value, value) != 0) {
-		cv->flags |= CONFIG_VALUE_CHANGED;
+    if(strcmp(cv->value, value) != 0) {
+        cv->flags |= CONFIG_VALUE_CHANGED;
 
-		free(cv->value);
-		cv->value = strdup(value);
-		if(!cv->value) fatal("Cannot allocate config.value");
-	}
+        freez(cv->value);
+        cv->value = strdupz(value);
+    }
 
-	return cv->value;
+    return cv->value;
 }
 
-const char *config_set(const char *section, const char *name, const char *value)
+const char *appconfig_set(struct config *root, const char *section, const char *name, const char *value)
 {
-	struct config_value *cv;
+    struct config_option *cv;
 
-	debug(D_CONFIG, "request to set config in section '%s', name '%s', value '%s'", section, name, value);
+    debug(D_CONFIG, "request to set config in section '%s', name '%s', value '%s'", section, name, value);
 
-	struct config *co = config_find_section(section);
-	if(!co) co = config_create(section);
+    struct section *co = appconfig_section_find(root, section);
+    if(!co) co = appconfig_section_create(root, section);
 
-	cv = config_value_index_find(co, name, 0);
-	if(!cv) cv = config_value_create(co, name, value);
-	cv->flags |= CONFIG_VALUE_USED;
+    cv = appconfig_option_index_find(co, name, 0);
+    if(!cv) cv = appconfig_value_create(co, name, value);
+    cv->flags |= CONFIG_VALUE_USED;
 
-	if(strcmp(cv->value, value) != 0) {
-		cv->flags |= CONFIG_VALUE_CHANGED;
+    if(strcmp(cv->value, value) != 0) {
+        cv->flags |= CONFIG_VALUE_CHANGED;
 
-		free(cv->value);
-		cv->value = strdup(value);
-		if(!cv->value) fatal("Cannot allocate config.value");
-	}
+        freez(cv->value);
+        cv->value = strdupz(value);
+    }
 
-	return value;
+    return value;
 }
 
-long long config_set_number(const char *section, const char *name, long long value)
+long long appconfig_set_number(struct config *root, const char *section, const char *name, long long value)
 {
-	char buffer[100];
-	sprintf(buffer, "%lld", value);
+    char buffer[100];
+    sprintf(buffer, "%lld", value);
 
-	config_set(section, name, buffer);
+    appconfig_set(root, section, name, buffer);
 
-	return value;
+    return value;
 }
 
-int config_set_boolean(const char *section, const char *name, int value)
+int appconfig_set_boolean(struct config *root, const char *section, const char *name, int value)
 {
-	char *s;
-	if(value) s = "yes";
-	else s = "no";
+    char *s;
+    if(value) s = "yes";
+    else s = "no";
 
-	config_set(section, name, s);
+    appconfig_set(root, section, name, s);
 
-	return value;
+    return value;
 }
 
-void generate_config(BUFFER *wb, int only_changed)
+
+// ----------------------------------------------------------------------------
+// config load/save
+
+int appconfig_load(struct config *root, char *filename, int overwrite_used)
 {
-	int i, pri;
-	struct config *co;
-	struct config_value *cv;
-
-	for(i = 0; i < 3 ;i++) {
-		switch(i) {
-			case 0:
-				buffer_strcat(wb,
-					"# NetData Configuration\n"
-					"# You can uncomment and change any of the options below.\n"
-					"# The value shown in the commented settings, is the default value.\n"
-					"\n# global netdata configuration\n");
-				break;
-
-			case 1:
-				buffer_strcat(wb, "\n\n# per plugin configuration\n");
-				break;
-
-			case 2:
-				buffer_strcat(wb, "\n\n# per chart configuration\n");
-				break;
-		}
-
-		pthread_rwlock_wrlock(&config_rwlock);
-		for(co = config_root; co ; co = co->next) {
-			if(strcmp(co->name, "global") == 0 || strcmp(co->name, "plugins") == 0) pri = 0;
-			else if(strncmp(co->name, "plugin:", 7) == 0) pri = 1;
-			else pri = 2;
-
-			if(i == pri) {
-				int used = 0;
-				int changed = 0;
-				int count = 0;
-
-				pthread_rwlock_wrlock(&co->rwlock);
-
-				for(cv = co->values; cv ; cv = cv->next) {
-					used += (cv->flags && CONFIG_VALUE_USED)?1:0;
-					changed += (cv->flags & CONFIG_VALUE_CHANGED)?1:0;
-					count++;
-				}
-
-				pthread_rwlock_unlock(&co->rwlock);
-
-				if(!count) continue;
-				if(only_changed && !changed) continue;
-
-				if(!used) {
-					buffer_sprintf(wb, "\n# node '%s' is not used.", co->name);
-				}
-
-				buffer_sprintf(wb, "\n[%s]\n", co->name);
-
-				pthread_rwlock_wrlock(&co->rwlock);
-				for(cv = co->values; cv ; cv = cv->next) {
-
-					if(used && !(cv->flags & CONFIG_VALUE_USED)) {
-						buffer_sprintf(wb, "\n\t# option '%s' is not used.\n", cv->name);
-					}
-					buffer_sprintf(wb, "\t%s%s = %s\n", ((!(cv->flags & CONFIG_VALUE_CHANGED)) && (cv->flags & CONFIG_VALUE_USED))?"# ":"", cv->name, cv->value);
-				}
-				pthread_rwlock_unlock(&co->rwlock);
-			}
-		}
-		pthread_rwlock_unlock(&config_rwlock);
-	}
+    int line = 0;
+    struct section *co = NULL;
+
+    char buffer[CONFIG_FILE_LINE_MAX + 1], *s;
+
+    if(!filename) filename = CONFIG_DIR "/" CONFIG_FILENAME;
+
+    debug(D_CONFIG, "Opening config file '%s'", filename);
+
+    FILE *fp = fopen(filename, "r");
+    if(!fp) {
+        error("Cannot open file '%s'", filename);
+        return 0;
+    }
+
+    while(fgets(buffer, CONFIG_FILE_LINE_MAX, fp) != NULL) {
+        buffer[CONFIG_FILE_LINE_MAX] = '\0';
+        line++;
+
+        s = trim(buffer);
+        if(!s) {
+            debug(D_CONFIG, "Ignoring line %d, it is empty.", line);
+            continue;
+        }
+
+        int len = (int) strlen(s);
+        if(*s == '[' && s[len - 1] == ']') {
+            // new section
+            s[len - 1] = '\0';
+            s++;
+
+            co = appconfig_section_find(root, s);
+            if(!co) co = appconfig_section_create(root, s);
+
+            continue;
+        }
+
+        if(!co) {
+            // line outside a section
+            error("Ignoring line %d ('%s'), it is outside all sections.", line, s);
+            continue;
+        }
+
+        char *name = s;
+        char *value = strchr(s, '=');
+        if(!value) {
+            error("Ignoring line %d ('%s'), there is no = in it.", line, s);
+            continue;
+        }
+        *value = '\0';
+        value++;
+
+        name = trim(name);
+        value = trim(value);
+
+        if(!name) {
+            error("Ignoring line %d, name is empty.", line);
+            continue;
+        }
+        if(!value) {
+            debug(D_CONFIG, "Ignoring line %d, value is empty.", line);
+            continue;
+        }
+
+        struct config_option *cv = appconfig_option_index_find(co, name, 0);
+
+        if(!cv) cv = appconfig_value_create(co, name, value);
+        else {
+            if(((cv->flags & CONFIG_VALUE_USED) && overwrite_used) || !(cv->flags & CONFIG_VALUE_USED)) {
+                debug(D_CONFIG, "Line %d, overwriting '%s/%s'.", line, co->name, cv->name);
+                freez(cv->value);
+                cv->value = strdupz(value);
+            }
+            else
+                debug(D_CONFIG, "Ignoring line %d, '%s/%s' is already present and used.", line, co->name, cv->name);
+        }
+        cv->flags |= CONFIG_VALUE_LOADED;
+    }
+
+    fclose(fp);
+
+    return 1;
 }
 
+void appconfig_generate(struct config *root, BUFFER *wb, int only_changed)
+{
+    int i, pri;
+    struct section *co;
+    struct config_option *cv;
+
+    for(i = 0; i < 3 ;i++) {
+        switch(i) {
+            case 0:
+                buffer_strcat(wb,
+                    "# netdata configuration\n"
+                    "#\n"
+                    "# You can download the latest version of this file, using:\n"
+                    "#\n"
+                    "#  wget -O /etc/netdata/netdata.conf http://localhost:19999/netdata.conf\n"
+                    "# or\n"
+                    "#  curl -o /etc/netdata/netdata.conf http://localhost:19999/netdata.conf\n"
+                    "#\n"
+                    "# You can uncomment and change any of the options below.\n"
+                    "# The value shown in the commented settings, is the default value.\n"
+                    "#\n"
+                    "\n# global netdata configuration\n");
+                break;
+
+            case 1:
+                buffer_strcat(wb, "\n\n# per plugin configuration\n");
+                break;
+
+            case 2:
+                buffer_strcat(wb, "\n\n# per chart configuration\n");
+                break;
+        }
+
+        appconfig_wrlock(root);
+        for(co = root->sections; co ; co = co->next) {
+            if(!strcmp(co->name, CONFIG_SECTION_GLOBAL)
+               || !strcmp(co->name, CONFIG_SECTION_WEB)
+               || !strcmp(co->name, CONFIG_SECTION_PLUGINS)
+               || !strcmp(co->name, CONFIG_SECTION_REGISTRY)
+               || !strcmp(co->name, CONFIG_SECTION_HEALTH)
+               || !strcmp(co->name, CONFIG_SECTION_BACKEND)
+               || !strcmp(co->name, CONFIG_SECTION_STREAM)
+                    )
+                pri = 0;
+            else if(!strncmp(co->name, "plugin:", 7)) pri = 1;
+            else pri = 2;
+
+            if(i == pri) {
+                int used = 0;
+                int changed = 0;
+                int count = 0;
+
+                config_section_wrlock(co);
+                for(cv = co->values; cv ; cv = cv->next) {
+                    used += (cv->flags & CONFIG_VALUE_USED)?1:0;
+                    changed += (cv->flags & CONFIG_VALUE_CHANGED)?1:0;
+                    count++;
+                }
+                config_section_unlock(co);
+
+                if(!count) continue;
+                if(only_changed && !changed) continue;
+
+                if(!used) {
+                    buffer_sprintf(wb, "\n# section '%s' is not used.", co->name);
+                }
+
+                buffer_sprintf(wb, "\n[%s]\n", co->name);
+
+                config_section_wrlock(co);
+                for(cv = co->values; cv ; cv = cv->next) {
+
+                    if(used && !(cv->flags & CONFIG_VALUE_USED)) {
+                        buffer_sprintf(wb, "\n\t# option '%s' is not used.\n", cv->name);
+                    }
+                    buffer_sprintf(wb, "\t%s%s = %s\n", ((!(cv->flags & CONFIG_VALUE_CHANGED)) && (cv->flags & CONFIG_VALUE_USED))?"# ":"", cv->name, cv->value);
+                }
+                config_section_unlock(co);
+            }
+        }
+        appconfig_unlock(root);
+    }
+}