pkgconf/libpkgconf/dependency.c

488 lines
14 KiB
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);
}