kc3-lang/pkgconf/libpkgconf/dependency.c

• Show log

  Commit

• Hash : 34b11020
  Author :
  Date : 2022-08-04T11:53:02
  

  dependency: zero list after freeing
  

Download

• libpkgconf/dependency.c

• /*
   * dependency.c
   * dependency parsing and management
   *
   * Copyright (c) 2011, 2012, 2013 pkgconf authors (see AUTHORS).
   *
   * Permission to use, copy, modify, and/or distribute this software for any
   * purpose with or without fee is hereby granted, provided that the above
   * copyright notice and this permission notice appear in all copies.
   *
   * This software is provided 'as is' and without any warranty, express or
   * implied.  In no event shall the authors be liable for any damages arising
   * from the use of this software.
   */
  
  #include <libpkgconf/stdinc.h>
  #include <libpkgconf/libpkgconf.h>
  
  /*
   * !doc
   *
   * libpkgconf `dependency` module
   * ==============================
   *
   * The `dependency` module provides support for building `dependency lists` (the basic component of the overall `dependency graph`) and
   * `dependency nodes` which store dependency information.
   */
  
  typedef enum {
  	OUTSIDE_MODULE = 0,
  	INSIDE_MODULE_NAME = 1,
  	BEFORE_OPERATOR = 2,
  	INSIDE_OPERATOR = 3,
  	AFTER_OPERATOR = 4,
  	INSIDE_VERSION = 5
  } parse_state_t;
  
  #define DEBUG_PARSE 0
  
  static const char *
  dependency_to_str(const pkgconf_dependency_t *dep, char *buf, size_t buflen)
  {
  	pkgconf_strlcpy(buf, dep->package, buflen);
  	if (dep->version != NULL)
  	{
  		pkgconf_strlcat(buf, " ", buflen);
  		pkgconf_strlcat(buf, pkgconf_pkg_get_comparator(dep), buflen);
  		pkgconf_strlcat(buf, " ", buflen);
  		pkgconf_strlcat(buf, dep->version, buflen);
  	}
  
  	return buf;
  }
  
  /* find a colliding dependency that is coloured differently */
  static inline pkgconf_dependency_t *
  find_colliding_dependency(const pkgconf_dependency_t *dep, const pkgconf_list_t *list)
  {
  	const pkgconf_node_t *n;
  
  	PKGCONF_FOREACH_LIST_ENTRY(list->head, n)
  	{
  		pkgconf_dependency_t *dep2 = n->data;
  
  		if (strcmp(dep->package, dep2->package))
  			continue;
  
  		if (dep->flags != dep2->flags)
  			return dep2;
  	}
  
  	return NULL;
  }
  
  static inline pkgconf_dependency_t *
  add_or_replace_dependency_node(pkgconf_client_t *client, pkgconf_dependency_t *dep, pkgconf_list_t *list)
  {
  	char depbuf[PKGCONF_ITEM_SIZE];
  	pkgconf_dependency_t *dep2 = find_colliding_dependency(dep, list);
  
  	/* there is already a node in the graph which describes this dependency */
  	if (dep2 != NULL)
  	{
  		char depbuf2[PKGCONF_ITEM_SIZE];
  
  		PKGCONF_TRACE(client, "dependency collision: [%s/%x] -- [%s/%x]",
  			      dependency_to_str(dep, depbuf, sizeof depbuf), dep->flags,
  			      dependency_to_str(dep2, depbuf2, sizeof depbuf2), dep2->flags);
  
  		/* prefer the uncoloured node, either dep or dep2 */
  		if (dep->flags && dep2->flags == 0)
  		{
  			PKGCONF_TRACE(client, "dropping dependency [%s]@%p because of collision", depbuf, dep);
  
  			pkgconf_dependency_unref(dep->owner, dep);
  			return NULL;
  		}
  		else if (dep2->flags && dep->flags == 0)
  		{
  			PKGCONF_TRACE(client, "dropping dependency [%s]@%p because of collision", depbuf2, dep2);
  
  			pkgconf_node_delete(&dep2->iter, list);
  			pkgconf_dependency_unref(dep2->owner, dep2);
  		}
  		else
  			/* If both dependencies have equal strength, we keep both, because of situations like:
  			 *    Requires: foo > 1, foo < 3
  			 *
  			 * If the situation is that both dependencies are literally equal, it is still harmless because
  			 * fragment deduplication will handle the excessive fragments.
  			 */
  			PKGCONF_TRACE(client, "keeping both dependencies (harmless)");
  	}
  
  	PKGCONF_TRACE(client, "added dependency [%s] to list @%p; flags=%x", dependency_to_str(dep, depbuf, sizeof depbuf), list, dep->flags);
  	pkgconf_node_insert_tail(&dep->iter, pkgconf_dependency_ref(dep->owner, dep), list);
  
  	/* This dependency is intentionally unowned.
  	 *
  	 * Internally we have no use for the returned type, and usually just
  	 * discard it. However, there is a publig pkgconf_dependency_add
  	 * function, which references this return value before returning it,
  	 * giving ownership at that point.
  	 */
  	return dep;
  }
  
  static inline pkgconf_dependency_t *
  pkgconf_dependency_addraw(pkgconf_client_t *client, pkgconf_list_t *list, const char *package, size_t package_sz, const char *version, size_t version_sz, pkgconf_pkg_comparator_t compare, unsigned int flags)
  {
  	pkgconf_dependency_t *dep;
  
  	dep = calloc(sizeof(pkgconf_dependency_t), 1);
  	dep->package = pkgconf_strndup(package, package_sz);
  
  	if (version_sz != 0)
  		dep->version = pkgconf_strndup(version, version_sz);
  
  	dep->compare = compare;
  	dep->flags = flags;
  	dep->owner = client;
  	dep->refcount = 0;
  
  	return add_or_replace_dependency_node(client, dep, list);
  }
  
  /*
   * !doc
   *
   * .. c:function:: pkgconf_dependency_t *pkgconf_dependency_add(pkgconf_list_t *list, const char *package, const char *version, pkgconf_pkg_comparator_t compare)
   *
   *    Adds a parsed dependency to a dependency list as a dependency node.
   *
   *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
   *    :param pkgconf_list_t* list: The dependency list to add a dependency node to.
   *    :param char* package: The package `atom` to set on the dependency node.
   *    :param char* version: The package `version` to set on the dependency node.
   *    :param pkgconf_pkg_comparator_t compare: The comparison operator to set on the dependency node.
   *    :param uint flags: Any flags to attach to the dependency node.
   *    :return: A dependency node.
   *    :rtype: pkgconf_dependency_t *
   */
  pkgconf_dependency_t *
  pkgconf_dependency_add(pkgconf_client_t *client, pkgconf_list_t *list, const char *package, const char *version, pkgconf_pkg_comparator_t compare, unsigned int flags)
  {
  	pkgconf_dependency_t *dep;
  	dep = pkgconf_dependency_addraw(client, list, package, strlen(package), version,
  					version != NULL ? strlen(version) : 0, compare, flags);
  	return pkgconf_dependency_ref(dep->owner, dep);
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_append(pkgconf_list_t *list, pkgconf_dependency_t *tail)
   *
   *    Adds a dependency node to a pre-existing dependency list.
   *
   *    :param pkgconf_list_t* list: The dependency list to add a dependency node to.
   *    :param pkgconf_dependency_t* tail: The dependency node to add to the tail of the dependency list.
   *    :return: nothing
   */
  void
  pkgconf_dependency_append(pkgconf_list_t *list, pkgconf_dependency_t *tail)
  {
  	pkgconf_node_insert_tail(&tail->iter, tail, list);
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_free_one(pkgconf_dependency_t *dep)
   *
   *    Frees a dependency node.
   *
   *    :param pkgconf_dependency_t* dep: The dependency node to free.
   *    :return: nothing
   */
  void
  pkgconf_dependency_free_one(pkgconf_dependency_t *dep)
  {
  	if (dep->match != NULL)
  		pkgconf_pkg_unref(dep->match->owner, dep->match);
  
  	if (dep->package != NULL)
  		free(dep->package);
  
  	if (dep->version != NULL)
  		free(dep->version);
  
  	free(dep);
  }
  
  /*
   * !doc
   *
   * .. c:function:: pkgconf_dependency_t *pkgconf_dependency_ref(pkgconf_client_t *owner, pkgconf_dependency_t *dep)
   *
   *    Increases a dependency node's refcount.
   *
   *    :param pkgconf_client_t* owner: The client object which owns the memory of this dependency node.
   *    :param pkgconf_dependency_t* dep: The dependency to increase the refcount of.
   *    :return: the dependency node on success, else NULL
   */
  pkgconf_dependency_t *
  pkgconf_dependency_ref(pkgconf_client_t *client, pkgconf_dependency_t *dep)
  {
  	if (client != dep->owner)
  		return NULL;
  
  	dep->refcount++;
  	PKGCONF_TRACE(client, "%s refcount@%p: %d", dep->package, dep, dep->refcount);
  	return dep;
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_unref(pkgconf_client_t *owner, pkgconf_dependency_t *dep)
   *
   *    Decreases a dependency node's refcount and frees it if necessary.
   *
   *    :param pkgconf_client_t* owner: The client object which owns the memory of this dependency node.
   *    :param pkgconf_dependency_t* dep: The dependency to decrease the refcount of.
   *    :return: nothing
   */
  void
  pkgconf_dependency_unref(pkgconf_client_t *client, pkgconf_dependency_t *dep)
  {
  	if (client != dep->owner)
  		return;
  
  	--dep->refcount;
  	PKGCONF_TRACE(client, "%s refcount@%p: %d", dep->package, dep, dep->refcount);
  
  	if (dep->refcount <= 0)
  		pkgconf_dependency_free_one(dep);
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_free(pkgconf_list_t *list)
   *
   *    Release a dependency list and it's child dependency nodes.
   *
   *    :param pkgconf_list_t* list: The dependency list to release.
   *    :return: nothing
   */
  void
  pkgconf_dependency_free(pkgconf_list_t *list)
  {
  	pkgconf_node_t *node, *next;
  
  	PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
  	{
  		pkgconf_dependency_t *dep = node->data;
  
  		pkgconf_node_delete(&dep->iter, list);
  		pkgconf_dependency_unref(dep->owner, dep);
  	}
  
  	pkgconf_list_zero(list);
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_parse_str(pkgconf_list_t *deplist_head, const char *depends)
   *
   *    Parse a dependency declaration into a dependency list.
   *    Commas are counted as whitespace to allow for constructs such as ``@SUBSTVAR@, zlib`` being processed
   *    into ``, zlib``.
   *
   *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
   *    :param pkgconf_list_t* deplist_head: The dependency list to populate with dependency nodes.
   *    :param char* depends: The dependency data to parse.
   *    :param uint flags: Any flags to attach to the dependency nodes.
   *    :return: nothing
   */
  void
  pkgconf_dependency_parse_str(pkgconf_client_t *client, pkgconf_list_t *deplist_head, const char *depends, unsigned int flags)
  {
  	parse_state_t state = OUTSIDE_MODULE;
  	pkgconf_pkg_comparator_t compare = PKGCONF_CMP_ANY;
  	char cmpname[PKGCONF_ITEM_SIZE];
  	char buf[PKGCONF_BUFSIZE];
  	size_t package_sz = 0, version_sz = 0;
  	char *start = buf;
  	char *ptr = buf;
  	char *vstart = NULL;
  	char *package = NULL, *version = NULL;
  	char *cnameptr = cmpname;
  	char *cnameend = cmpname + PKGCONF_ITEM_SIZE - 1;
  
  	memset(cmpname, '\0', sizeof cmpname);
  
  	pkgconf_strlcpy(buf, depends, sizeof buf);
  	pkgconf_strlcat(buf, " ", sizeof buf);
  
  	while (*ptr)
  	{
  		switch (state)
  		{
  		case OUTSIDE_MODULE:
  			if (!PKGCONF_IS_MODULE_SEPARATOR(*ptr))
  				state = INSIDE_MODULE_NAME;
  
  			break;
  
  		case INSIDE_MODULE_NAME:
  			if (isspace((unsigned int)*ptr))
  			{
  				const char *sptr = ptr;
  
  				while (*sptr && isspace((unsigned int)*sptr))
  					sptr++;
  
  				if (*sptr == '\0')
  					state = OUTSIDE_MODULE;
  				else if (PKGCONF_IS_MODULE_SEPARATOR(*sptr))
  					state = OUTSIDE_MODULE;
  				else if (PKGCONF_IS_OPERATOR_CHAR(*sptr))
  					state = BEFORE_OPERATOR;
  				else
  					state = OUTSIDE_MODULE;
  			}
  			else if (PKGCONF_IS_MODULE_SEPARATOR(*ptr))
  				state = OUTSIDE_MODULE;
  			else if (*(ptr + 1) == '\0')
  			{
  				ptr++;
  				state = OUTSIDE_MODULE;
  			}
  
  			if (state != INSIDE_MODULE_NAME && start != ptr)
  			{
  				char *iter = start;
  
  				while (PKGCONF_IS_MODULE_SEPARATOR(*iter))
  					iter++;
  
  				package = iter;
  				package_sz = ptr - iter;
  				start = ptr;
  			}
  
  			if (state == OUTSIDE_MODULE)
  			{
  				pkgconf_dependency_addraw(client, deplist_head, package, package_sz, NULL, 0, compare, flags);
  
  				compare = PKGCONF_CMP_ANY;
  				package_sz = 0;
  			}
  
  			break;
  
  		case BEFORE_OPERATOR:
  			if (PKGCONF_IS_OPERATOR_CHAR(*ptr))
  			{
  				state = INSIDE_OPERATOR;
  				if (cnameptr < cnameend)
  					*cnameptr++ = *ptr;
  			}
  
  			break;
  
  		case INSIDE_OPERATOR:
  			if (!PKGCONF_IS_OPERATOR_CHAR(*ptr))
  			{
  				state = AFTER_OPERATOR;
  				compare = pkgconf_pkg_comparator_lookup_by_name(cmpname);
  			}
  			else if (cnameptr < cnameend)
  				*cnameptr++ = *ptr;
  
  			break;
  
  		case AFTER_OPERATOR:
  			if (!isspace((unsigned int)*ptr))
  			{
  				vstart = ptr;
  				state = INSIDE_VERSION;
  			}
  			break;
  
  		case INSIDE_VERSION:
  			if (PKGCONF_IS_MODULE_SEPARATOR(*ptr) || *(ptr + 1) == '\0')
  			{
  				version = vstart;
  				version_sz = ptr - vstart;
  				state = OUTSIDE_MODULE;
  
  				pkgconf_dependency_addraw(client, deplist_head, package, package_sz, version, version_sz, compare, flags);
  
  				compare = PKGCONF_CMP_ANY;
  				cnameptr = cmpname;
  				memset(cmpname, 0, sizeof cmpname);
  				package_sz = 0;
  			}
  
  			if (state == OUTSIDE_MODULE)
  				start = ptr;
  			break;
  		}
  
  		ptr++;
  	}
  }
  
  /*
   * !doc
   *
   * .. c:function:: void pkgconf_dependency_parse(const pkgconf_client_t *client, pkgconf_pkg_t *pkg, pkgconf_list_t *deplist, const char *depends)
   *
   *    Preprocess dependency data and then process that dependency declaration into a dependency list.
   *    Commas are counted as whitespace to allow for constructs such as ``@SUBSTVAR@, zlib`` being processed
   *    into ``, zlib``.
   *
   *    :param pkgconf_client_t* client: The client object that owns the package this dependency list belongs to.
   *    :param pkgconf_pkg_t* pkg: The package object that owns this dependency list.
   *    :param pkgconf_list_t* deplist: The dependency list to populate with dependency nodes.
   *    :param char* depends: The dependency data to parse.
   *    :param uint flags: Any flags to attach to the dependency nodes.
   *    :return: nothing
   */
  void
  pkgconf_dependency_parse(pkgconf_client_t *client, pkgconf_pkg_t *pkg, pkgconf_list_t *deplist, const char *depends, unsigned int flags)
  {
  	char *kvdepends = pkgconf_tuple_parse(client, &pkg->vars, depends, pkg->flags);
  
  	pkgconf_dependency_parse_str(client, deplist, kvdepends, flags);
  	free(kvdepends);
  }
  
  /*
   * !doc
   *
   * .. c:function:: pkgconf_dependency_t *pkgconf_dependency_copy(pkgconf_client_t *client, const pkgconf_dependency_t *dep)
   *
   *    Copies a dependency node to a new one.
   *
   *    :param pkgconf_client_t* client: The client object that will own this dependency.
   *    :param pkgconf_dependency_t* dep: The dependency node to copy.
   *    :return: a pointer to a new dependency node, else NULL
   */
  pkgconf_dependency_t *
  pkgconf_dependency_copy(pkgconf_client_t *client, const pkgconf_dependency_t *dep)
  {
  	pkgconf_dependency_t *new_dep;
  
  	new_dep = calloc(sizeof(pkgconf_dependency_t), 1);
  	new_dep->package = strdup(dep->package);
  
  	if (dep->version != NULL)
  		new_dep->version = strdup(dep->version);
  
  	new_dep->compare = dep->compare;
  	new_dep->flags = dep->flags;
  	new_dep->owner = client;
  	new_dep->refcount = 0;
  
  	if (dep->match != NULL)
  		new_dep->match = pkgconf_pkg_ref(client, dep->match);
  
  	return pkgconf_dependency_ref(client, new_dep);
  }
  

Download