zconfig(3)
CZMQ Manual - CZMQ/4.2.0
Name
zconfig - Class for work with config files written in rfc.zeromq.org/spec:4/ZPL.
Synopsis
// This is a stable class, and may not change except for emergencies. It
// is provided in stable builds.
// This class has draft methods, which may change over time. They are not
// in stable releases, by default. Use --enable-drafts to enable.
//
typedef int (zconfig_fct) (
zconfig_t *self, void *arg, int level);
// Create new config item
CZMQ_EXPORT zconfig_t *
zconfig_new (const char *name, zconfig_t *parent);
// Load a config tree from a specified ZPL text file; returns a zconfig_t
// reference for the root, if the file exists and is readable. Returns NULL
// if the file does not exist.
CZMQ_EXPORT zconfig_t *
zconfig_load (const char *filename);
// Equivalent to zconfig_load, taking a format string instead of a fixed
// filename.
CZMQ_EXPORT zconfig_t *
zconfig_loadf (const char *format, ...) CHECK_PRINTF (1);
// Destroy a config item and all its children
CZMQ_EXPORT void
zconfig_destroy (zconfig_t **self_p);
// Return name of config item
CZMQ_EXPORT char *
zconfig_name (zconfig_t *self);
// Return value of config item
CZMQ_EXPORT char *
zconfig_value (zconfig_t *self);
// Insert or update configuration key with value
CZMQ_EXPORT void
zconfig_put (zconfig_t *self, const char *path, const char *value);
// Equivalent to zconfig_put, accepting a format specifier and variable
// argument list, instead of a single string value.
CZMQ_EXPORT void
zconfig_putf (zconfig_t *self, const char *path, const char *format, ...) CHECK_PRINTF (3);
// Get value for config item into a string value; leading slash is optional
// and ignored.
CZMQ_EXPORT char *
zconfig_get (zconfig_t *self, const char *path, const char *default_value);
// Set config item name, name may be NULL
CZMQ_EXPORT void
zconfig_set_name (zconfig_t *self, const char *name);
// Set new value for config item. The new value may be a string, a printf
// format, or NULL. Note that if string may possibly contain '%', or if it
// comes from an insecure source, you must use '%s' as the format, followed
// by the string.
CZMQ_EXPORT void
zconfig_set_value (zconfig_t *self, const char *format, ...) CHECK_PRINTF (2);
// Find our first child, if any
CZMQ_EXPORT zconfig_t *
zconfig_child (zconfig_t *self);
// Find our first sibling, if any
CZMQ_EXPORT zconfig_t *
zconfig_next (zconfig_t *self);
// Find a config item along a path; leading slash is optional and ignored.
CZMQ_EXPORT zconfig_t *
zconfig_locate (zconfig_t *self, const char *path);
// Locate the last config item at a specified depth
CZMQ_EXPORT zconfig_t *
zconfig_at_depth (zconfig_t *self, int level);
// Execute a callback for each config item in the tree; returns zero if
// successful, else -1.
CZMQ_EXPORT int
zconfig_execute (zconfig_t *self, zconfig_fct handler, void *arg);
// Add comment to config item before saving to disk. You can add as many
// comment lines as you like. If you use a null format, all comments are
// deleted.
CZMQ_EXPORT void
zconfig_set_comment (zconfig_t *self, const char *format, ...) CHECK_PRINTF (2);
// Return comments of config item, as zlist.
CZMQ_EXPORT zlist_t *
zconfig_comments (zconfig_t *self);
// Save a config tree to a specified ZPL text file, where a filename
// "-" means dump to standard output.
CZMQ_EXPORT int
zconfig_save (zconfig_t *self, const char *filename);
// Equivalent to zconfig_save, taking a format string instead of a fixed
// filename.
CZMQ_EXPORT int
zconfig_savef (zconfig_t *self, const char *format, ...) CHECK_PRINTF (2);
// Report filename used during zconfig_load, or NULL if none
CZMQ_EXPORT const char *
zconfig_filename (zconfig_t *self);
// Reload config tree from same file that it was previously loaded from.
// Returns 0 if OK, -1 if there was an error (and then does not change
// existing data).
CZMQ_EXPORT int
zconfig_reload (zconfig_t **self_p);
// Load a config tree from a memory chunk
CZMQ_EXPORT zconfig_t *
zconfig_chunk_load (zchunk_t *chunk);
// Save a config tree to a new memory chunk
CZMQ_EXPORT zchunk_t *
zconfig_chunk_save (zconfig_t *self);
// Load a config tree from a null-terminated string
// Caller owns return value and must destroy it when done.
CZMQ_EXPORT zconfig_t *
zconfig_str_load (const char *string);
// Save a config tree to a new null terminated string
// Caller owns return value and must destroy it when done.
CZMQ_EXPORT char *
zconfig_str_save (zconfig_t *self);
// Return true if a configuration tree was loaded from a file and that
// file has changed in since the tree was loaded.
CZMQ_EXPORT bool
zconfig_has_changed (zconfig_t *self);
// Print the config file to open stream
CZMQ_EXPORT void
zconfig_fprint (zconfig_t *self, FILE *file);
// Print properties of object
CZMQ_EXPORT void
zconfig_print (zconfig_t *self);
// Self test of this class
CZMQ_EXPORT void
zconfig_test (bool verbose);
#ifdef CZMQ_BUILD_DRAFT_API
// *** Draft method, for development use, may change without warning ***
// Create copy of zconfig, caller MUST free the value
// Create copy of config, as new zconfig object. Returns a fresh zconfig_t
// object. If config is null, or memory was exhausted, returns null.
// Caller owns return value and must destroy it when done.
CZMQ_EXPORT zconfig_t *
zconfig_dup (zconfig_t *self);
// *** Draft method, for development use, may change without warning ***
// Destroy subtree (all children)
CZMQ_EXPORT void
zconfig_remove_subtree (zconfig_t *self);
// *** Draft method, for development use, may change without warning ***
// Destroy node and subtree (all children)
CZMQ_EXPORT void
zconfig_remove (zconfig_t **self_p);
#endif // CZMQ_BUILD_DRAFT_API
Please add '@interface' section in './../src/zconfig.c'.
Description
Lets applications load, work with, and save configuration files. This implements rfc.zeromq.org/spec:4/ZPL, which is a simple structured text format for configuration files.
Here is an example ZPL stream and corresponding config structure:
context
iothreads = 1
verbose = 1 # Ask for a trace
main
type = zqueue # ZMQ_DEVICE type
frontend
option
hwm = 1000
swap = 25000000 # 25MB
bind = 'inproc:@@//@@addr1'
bind = 'ipc:@@//@@addr2'
backend
bind = inproc:@@//@@addr3
root Down = child
| Across = next
v
context-->main
| |
| v
| type=queue-->frontend-->backend
| | |
| | v
| | bind=inproc:@@//@@addr3
| v
| option-->bind=inproc:@@//@@addr1-->bind=ipc:@@//@@addr2
| |
| v
| hwm=1000-->swap=25000000
v
iothreads=1-->verbose=false
Example
From zconfig_test method
const char *SELFTEST_DIR_RW = "src/selftest-rw";
const char *testbasedir = ".test_zconfig";
const char *testfile = "test.cfg";
char *basedirpath = NULL; // subdir in a test, under SELFTEST_DIR_RW
char *filepath = NULL; // pathname to testfile in a test, in dirpath
basedirpath = zsys_sprintf ("%s/%s", SELFTEST_DIR_RW, testbasedir);
assert (basedirpath);
filepath = zsys_sprintf ("%s/%s", basedirpath, testfile);
assert (filepath);
// Make sure old aborted tests do not hinder us
zdir_t *dir = zdir_new (basedirpath, NULL);
if (dir) {
zdir_remove (dir, true);
zdir_destroy (&dir);
}
zsys_file_delete (filepath);
zsys_dir_delete (basedirpath);
// Create temporary directory for test files
zsys_dir_create (basedirpath);
zconfig_t *root = zconfig_new ("root", NULL);
assert (root);
zconfig_t *section, *item;
section = zconfig_new ("headers", root);
assert (section);
item = zconfig_new ("email", section);
assert (item);
zconfig_set_value (item, "some@random.com");
item = zconfig_new ("name", section);
assert (item);
zconfig_set_value (item, "Justin Kayce");
zconfig_putf (root, "/curve/secret-key", "%s", "Top Secret");
zconfig_set_comment (root, " CURVE certificate");
zconfig_set_comment (root, " -----------------");
assert (zconfig_comments (root));
zconfig_save (root, filepath);
zconfig_destroy (&root);
root = zconfig_load (filepath);
if (verbose)
zconfig_save (root, "-");
assert (streq (zconfig_filename (root), filepath));
char *email = zconfig_get (root, "/headers/email", NULL);
assert (email);
assert (streq (email, "some@random.com"));
char *passwd = zconfig_get (root, "/curve/secret-key", NULL);
assert (passwd);
assert (streq (passwd, "Top Secret"));
zconfig_savef (root, "%s/%s", basedirpath, testfile);
assert (!zconfig_has_changed (root));
int rc = zconfig_reload (&root);
assert (rc == 0);
assert (!zconfig_has_changed (root));
zconfig_destroy (&root);
// Test chunk load/save
root = zconfig_new ("root", NULL);
assert (root);
section = zconfig_new ("section", root);
assert (section);
item = zconfig_new ("value", section);
assert (item);
zconfig_set_value (item, "somevalue");
zconfig_t *search = zconfig_locate (root, "section/value");
assert (search == item);
zchunk_t *chunk = zconfig_chunk_save (root);
assert (strlen ((char *) zchunk_data (chunk)) == 32);
char *string = zconfig_str_save (root);
assert (string);
assert (streq (string, (char *) zchunk_data (chunk)));
freen (string);
assert (chunk);
zconfig_destroy (&root);
root = zconfig_chunk_load (chunk);
assert (root);
char *value = zconfig_get (root, "/section/value", NULL);
assert (value);
assert (streq (value, "somevalue"));
// Test config can't be saved to a file in a path that doesn't
// exist or isn't writable
rc = zconfig_savef (root, "%s/path/that/doesnt/exist/%s", basedirpath, testfile);
assert (rc == -1);
zconfig_destroy (&root);
zchunk_destroy (&chunk);
// Test str_load
zconfig_t *config = zconfig_str_load (
"malamute\n"
" endpoint = ipc://@/malamute\n"
" producer = STREAM\n"
" consumer\n"
" STREAM2 = .*\n"
" STREAM3 = HAM\n"
"server\n"
" verbose = true\n"
);
assert (config);
assert (streq (zconfig_get (config, "malamute/endpoint", NULL), "ipc://@/malamute"));
assert (streq (zconfig_get (config, "malamute/producer", NULL), "STREAM"));
assert (zconfig_locate (config, "malamute/consumer"));
zconfig_t *c = zconfig_child (zconfig_locate (config, "malamute/consumer"));
assert (c);
assert (streq (zconfig_name (c), "STREAM2"));
assert (streq (zconfig_value (c), ".*"));
c = zconfig_next (c);
assert (c);
assert (streq (zconfig_name (c), "STREAM3"));
assert (streq (zconfig_value (c), "HAM"));
c = zconfig_next (c);
assert (!c);
assert (streq (zconfig_get (config, "server/verbose", NULL), "true"));
zconfig_t *dup = zconfig_dup (config);
assert (dup);
assert (streq (zconfig_get (dup, "server/verbose", NULL), "true"));
zconfig_destroy (&dup);
zconfig_destroy (&config);
// Test subtree removal
{
zconfig_t *root = zconfig_str_load (
"context\n"
" iothreads = 1\n"
" verbose = 1 # Ask for a trace\n"
"main\n"
" type = zqueue # ZMQ_DEVICE type\n"
" frontend\n"
" option\n"
" hwm = 1000\n"
" swap = 25000000 # 25MB\n"
" bind = 'inproc://addr1'\n"
" bind = 'ipc://addr2'\n"
" backend\n"
" bind = inproc://addr3\n"
);
// no subtree
zconfig_t *to_delete = zconfig_locate (root, "context/iothreads");
assert (to_delete);
zconfig_remove_subtree (to_delete);
zconfig_t *check = zconfig_locate (root, "context/iothreads");
assert (check);
assert (streq (zconfig_value (check), "1"));
check = zconfig_locate (root, "context/verbose");
assert (check);
assert (streq (zconfig_value (check), "1"));
// existing subtree
to_delete = zconfig_locate (root, "main/frontend/option");
assert (to_delete);
zconfig_remove_subtree (to_delete);
check = zconfig_locate (root, "main/frontend/option/hwm");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend/option/swap");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend/option");
assert (check);
assert (streq (zconfig_value (check), ""));
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "bind"));
assert (streq (zconfig_value (check), "inproc://addr1"));
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "bind"));
assert (streq (zconfig_value (check), "ipc://addr2"));
assert (zconfig_next (check) == NULL);
to_delete = zconfig_locate (root, "main/frontend");
assert (to_delete);
zconfig_remove_subtree (to_delete);
check = zconfig_locate (root, "main/frontend/option/hwm");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend/option/swap");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend/option");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend/bind");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend");
assert (check);
assert (streq (zconfig_value (check), ""));
assert (zconfig_child (check) == NULL);
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "backend"));
assert (streq (zconfig_value (check), ""));
to_delete = zconfig_locate (root, "main");
assert (to_delete);
zconfig_remove_subtree (to_delete);
check = zconfig_locate (root, "main/type");
assert (check == NULL);
check = zconfig_locate (root, "main/frontend");
assert (check == NULL);
check = zconfig_locate (root, "main/backend");
assert (check == NULL);
check = zconfig_locate (root, "main");
assert (check);
// root
zconfig_remove_subtree (root);
assert (root);
assert (zconfig_child (root) == NULL);
check = zconfig_locate (root, "main");
assert (check == NULL);
check = zconfig_locate (root, "context");
assert (check == NULL);
zconfig_destroy (&root);
}
// Test node and subtree removal
{
zconfig_t *root = zconfig_str_load (
"A1 = abc\n"
" x\n"
" 1\n"
" 2\n"
" y = 1 # Ask for a trace\n"
"A2\n"
" B1 = zqueue # ZMQ_DEVICE type\n"
" B2\n"
" C1\n"
" hwm = 1000\n"
" swap = 25000000 # 25MB\n"
" C2 = 50\n"
" C3\n"
" bind = addr3\n"
" B3\n"
" bind = inproc://addr4\n"
" B4 = Ignac\n"
" z = 5\n"
"A3\n"
"A4\n"
);
zconfig_t *to_delete = zconfig_locate (root, "A2/B2/C3");
assert (to_delete);
zconfig_remove (&to_delete);
zconfig_t *check = zconfig_locate (root, "A2/B2/C2");
assert (check);
assert (streq (zconfig_value (check), "50"));
assert (zconfig_next (check) == NULL);
assert (zconfig_locate (root, "A2/B2/C3/bind") == NULL);
assert (zconfig_locate (root, "A2/B2/C3") == NULL);
to_delete = zconfig_locate (root, "A2/B2");
assert (to_delete);
zconfig_remove (&to_delete);
check = zconfig_locate (root, "A2");
assert (check);
check = zconfig_child (check);
assert (check);
assert (streq (zconfig_name (check), "B1"));
assert (streq (zconfig_value (check), "zqueue"));
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "B3"));
assert (streq (zconfig_value (check), ""));
assert (zconfig_locate (root, "A2/B2/C1") == NULL);
assert (zconfig_locate (root, "A2/B2/C2") == NULL);
assert (zconfig_locate (root, "A2/B2") == NULL);
assert (zconfig_locate (root, "A2/B4"));
to_delete = zconfig_locate (root, "A2/B1");
assert (to_delete);
zconfig_remove (&to_delete);
check = zconfig_locate (root, "A2");
assert (check);
check = zconfig_child (check);
assert (check);
assert (streq (zconfig_name (check), "B3"));
assert (streq (zconfig_value (check), ""));
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "B4"));
assert (streq (zconfig_value (check), "Ignac"));
assert (zconfig_next (check) == NULL);
assert (zconfig_locate (root, "A2/B1") == NULL);
assert (zconfig_locate (root, "A2/B2") == NULL);
to_delete = zconfig_locate (root, "A2/B3");
assert (to_delete);
zconfig_remove (&to_delete);
check = zconfig_locate (root, "A2");
assert (check);
check = zconfig_child (check);
assert (check);
assert (streq (zconfig_name (check), "B4"));
assert (streq (zconfig_value (check), "Ignac"));
assert (zconfig_next (check) == NULL);
to_delete = zconfig_locate (root, "A2");
assert (to_delete);
zconfig_remove (&to_delete);
check = zconfig_locate (root, "A1");
assert (check);
check = zconfig_next (check);
assert (check);
assert (streq (zconfig_name (check), "A3"));
assert (zconfig_locate (root, "A2/B4") == NULL);
assert (zconfig_locate (root, "A2") == NULL);
to_delete = zconfig_locate (root, "A1");
assert (to_delete);
zconfig_remove (&to_delete);
check = zconfig_child (root);
assert (check);
assert (streq (zconfig_name (check), "A3"));
assert (zconfig_locate (root, "A1/x/1") == NULL);
assert (zconfig_locate (root, "A1/x") == NULL);
assert (zconfig_locate (root, "A1/y") == NULL);
assert (zconfig_locate (root, "A3"));
assert (zconfig_locate (root, "A4"));
// called on root should be equivalent to zconfig_destroy (&root)
zconfig_remove (&root);
}
// Delete all test files
dir = zdir_new (basedirpath, NULL);
assert (dir);
zdir_remove (dir, true);
zdir_destroy (&dir);
zstr_free (&basedirpath);
zstr_free (&filepath);
#if defined (__WINDOWS__)
zsys_shutdown(); #endif
Authors
The czmq manual was written by the authors in the AUTHORS file.
Resources
Main web site:
Report bugs to the email <gro.qmorez.stsil|ved-qmorez#gro.qmorez.stsil|ved-qmorez>
Copyright
Copyright (c) the Contributors as noted in the AUTHORS file. This file is part of CZMQ, the high-level C binding for ØMQ: http://czmq.zeromq.org. This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. LICENSE included with the czmq distribution.