pkgconf/libpkgconf/tuple.c

477 lines
12 KiB
C

/*
* tuple.c
* management of key->value tuples
*
* Copyright (c) 2011, 2012 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 `tuple` module
* =========================
*
* The `tuple` module provides key-value mappings backed by a linked list. The key-value
* mapping is mainly used for variable substitution when parsing .pc files.
*
* There are two sets of mappings: a ``pkgconf_pkg_t`` specific mapping, and a `global` mapping.
* The `tuple` module provides convenience wrappers for managing the `global` mapping, which is
* attached to a given client object.
*/
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_add_global(pkgconf_client_t *client, const char *key, const char *value)
*
* Defines a global variable, replacing the previous declaration if one was set.
*
* :param pkgconf_client_t* client: The pkgconf client object to modify.
* :param char* key: The key for the mapping (variable name).
* :param char* value: The value for the mapped entry.
* :return: nothing
*/
void
pkgconf_tuple_add_global(pkgconf_client_t *client, const char *key, const char *value)
{
pkgconf_tuple_add(client, &client->global_vars, key, value, false, 0);
}
static pkgconf_tuple_t *
lookup_global_tuple(const pkgconf_client_t *client, const char *key)
{
pkgconf_node_t *node;
PKGCONF_FOREACH_LIST_ENTRY(client->global_vars.head, node)
{
pkgconf_tuple_t *tuple = node->data;
if (!strcmp(tuple->key, key))
return tuple;
}
return NULL;
}
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_find_global(const pkgconf_client_t *client, const char *key)
*
* Looks up a global variable.
*
* :param pkgconf_client_t* client: The pkgconf client object to access.
* :param char* key: The key or variable name to look up.
* :return: the contents of the variable or ``NULL``
* :rtype: char *
*/
char *
pkgconf_tuple_find_global(const pkgconf_client_t *client, const char *key)
{
pkgconf_tuple_t *tuple;
tuple = lookup_global_tuple(client, key);
if (tuple == NULL)
return NULL;
return tuple->value;
}
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_free_global(pkgconf_client_t *client)
*
* Delete all global variables associated with a pkgconf client object.
*
* :param pkgconf_client_t* client: The pkgconf client object to modify.
* :return: nothing
*/
void
pkgconf_tuple_free_global(pkgconf_client_t *client)
{
pkgconf_tuple_free(&client->global_vars);
}
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_define_global(pkgconf_client_t *client, const char *kv)
*
* Parse and define a global variable.
*
* :param pkgconf_client_t* client: The pkgconf client object to modify.
* :param char* kv: The variable in the form of ``key=value``.
* :return: nothing
*/
void
pkgconf_tuple_define_global(pkgconf_client_t *client, const char *kv)
{
char *workbuf = strdup(kv);
char *value;
pkgconf_tuple_t *tuple;
value = strchr(workbuf, '=');
if (value == NULL)
goto out;
*value++ = '\0';
tuple = pkgconf_tuple_add(client, &client->global_vars, workbuf, value, false, 0);
if (tuple != NULL)
tuple->flags = PKGCONF_PKG_TUPLEF_OVERRIDE;
out:
free(workbuf);
}
static void
pkgconf_tuple_find_delete(pkgconf_list_t *list, const char *key)
{
pkgconf_node_t *node, *next;
PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
{
pkgconf_tuple_t *tuple = node->data;
if (!strcmp(tuple->key, key))
{
pkgconf_tuple_free_entry(tuple, list);
return;
}
}
}
static char *
dequote(const char *value)
{
char *buf = calloc((strlen(value) + 1) * 2, 1);
char *bptr = buf;
const char *i;
char quote = 0;
if (*value == '\'' || *value == '"')
quote = *value;
for (i = value; *i != '\0'; i++)
{
if (*i == '\\' && quote && *(i + 1) == quote)
{
i++;
*bptr++ = *i;
}
else if (*i != quote)
*bptr++ = *i;
}
return buf;
}
static const char *
find_sysroot(const pkgconf_client_t *client, pkgconf_list_t *vars)
{
const char *sysroot_dir;
sysroot_dir = pkgconf_tuple_find(client, vars, "pc_sysrootdir");
if (sysroot_dir == NULL)
sysroot_dir = client->sysroot_dir;
return sysroot_dir;
}
static bool
should_rewrite_sysroot(const pkgconf_client_t *client, pkgconf_list_t *vars, const char *buf, unsigned int flags)
{
const char *sysroot_dir;
if (flags & PKGCONF_PKG_PROPF_UNINSTALLED && !(client->flags & PKGCONF_PKG_PKGF_FDO_SYSROOT_RULES))
return false;
sysroot_dir = find_sysroot(client, vars);
if (sysroot_dir == NULL)
return false;
if (*buf != '/')
return false;
if (!strcmp(sysroot_dir, "/"))
return false;
if (strlen(buf) <= strlen(sysroot_dir))
return false;
if (strstr(buf + strlen(sysroot_dir), sysroot_dir) == NULL)
return false;
return true;
}
/*
* !doc
*
* .. c:function:: pkgconf_tuple_t *pkgconf_tuple_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key, const char *value, bool parse)
*
* Optionally parse and then define a variable.
*
* :param pkgconf_client_t* client: The pkgconf client object to access.
* :param pkgconf_list_t* list: The variable list to add the new variable to.
* :param char* key: The name of the variable being added.
* :param char* value: The value of the variable being added.
* :param bool parse: Whether or not to parse the value for variable substitution.
* :return: a variable object
* :rtype: pkgconf_tuple_t *
*/
pkgconf_tuple_t *
pkgconf_tuple_add(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key, const char *value, bool parse, unsigned int flags)
{
char *dequote_value;
pkgconf_tuple_t *tuple = calloc(sizeof(pkgconf_tuple_t), 1);
pkgconf_tuple_find_delete(list, key);
dequote_value = dequote(value);
tuple->key = strdup(key);
if (parse)
tuple->value = pkgconf_tuple_parse(client, list, dequote_value, flags);
else
tuple->value = strdup(dequote_value);
PKGCONF_TRACE(client, "adding tuple to @%p: %s => %s (parsed? %d)", list, key, tuple->value, parse);
pkgconf_node_insert(&tuple->iter, tuple, list);
free(dequote_value);
return tuple;
}
/*
* !doc
*
* .. c:function:: char *pkgconf_tuple_find(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key)
*
* Look up a variable in a variable list.
*
* :param pkgconf_client_t* client: The pkgconf client object to access.
* :param pkgconf_list_t* list: The variable list to search.
* :param char* key: The variable name to search for.
* :return: the value of the variable or ``NULL``
* :rtype: char *
*/
char *
pkgconf_tuple_find(const pkgconf_client_t *client, pkgconf_list_t *list, const char *key)
{
pkgconf_node_t *node;
pkgconf_tuple_t *global_tuple;
global_tuple = lookup_global_tuple(client, key);
if (global_tuple != NULL && global_tuple->flags & PKGCONF_PKG_TUPLEF_OVERRIDE)
return global_tuple->value;
PKGCONF_FOREACH_LIST_ENTRY(list->head, node)
{
pkgconf_tuple_t *tuple = node->data;
if (!strcmp(tuple->key, key))
return tuple->value;
}
if (global_tuple != NULL)
return global_tuple->value;
return NULL;
}
/*
* !doc
*
* .. c:function:: char *pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const char *value, unsigned int flags)
*
* Parse an expression for variable substitution.
*
* :param pkgconf_client_t* client: The pkgconf client object to access.
* :param pkgconf_list_t* list: The variable list to search for variables (along side the global variable list).
* :param char* value: The ``key=value`` string to parse.
* :param uint flags: Any flags to consider while parsing.
* :return: the variable data with any variables substituted
* :rtype: char *
*/
char *
pkgconf_tuple_parse(const pkgconf_client_t *client, pkgconf_list_t *vars, const char *value, unsigned int flags)
{
char buf[PKGCONF_BUFSIZE];
const char *ptr;
char *bptr = buf;
if (!(client->flags & PKGCONF_PKG_PKGF_FDO_SYSROOT_RULES) &&
(!(flags & PKGCONF_PKG_PROPF_UNINSTALLED) || (client->flags & PKGCONF_PKG_PKGF_PKGCONF1_SYSROOT_RULES)))
{
if (*value == '/' && client->sysroot_dir != NULL && strncmp(value, client->sysroot_dir, strlen(client->sysroot_dir)))
bptr += pkgconf_strlcpy(buf, client->sysroot_dir, sizeof buf);
}
for (ptr = value; *ptr != '\0' && bptr - buf < PKGCONF_BUFSIZE; ptr++)
{
if (*ptr != '$' || (*ptr == '$' && *(ptr + 1) != '{'))
*bptr++ = *ptr;
else if (*(ptr + 1) == '{')
{
char varname[PKGCONF_ITEM_SIZE];
char *vend = varname + PKGCONF_ITEM_SIZE - 1;
char *vptr = varname;
const char *pptr;
char *kv, *parsekv;
*vptr = '\0';
for (pptr = ptr + 2; *pptr != '\0'; pptr++)
{
if (*pptr != '}')
{
if (vptr < vend)
*vptr++ = *pptr;
else
{
*vptr = '\0';
break;
}
}
else
{
*vptr = '\0';
break;
}
}
PKGCONF_TRACE(client, "lookup tuple %s", varname);
size_t remain = PKGCONF_BUFSIZE - (bptr - buf);
ptr += (pptr - ptr);
kv = pkgconf_tuple_find_global(client, varname);
if (kv != NULL)
{
size_t nlen = pkgconf_strlcpy(bptr, kv, remain);
if (nlen > remain)
{
pkgconf_warn(client, "warning: truncating very long variable to 64KB\n");
bptr = buf + (PKGCONF_BUFSIZE - 1);
break;
}
bptr += nlen;
}
else
{
kv = pkgconf_tuple_find(client, vars, varname);
if (kv != NULL)
{
size_t nlen;
parsekv = pkgconf_tuple_parse(client, vars, kv, flags);
nlen = pkgconf_strlcpy(bptr, parsekv, remain);
free(parsekv);
if (nlen > remain)
{
pkgconf_warn(client, "warning: truncating very long variable to 64KB\n");
bptr = buf + (PKGCONF_BUFSIZE - 1);
break;
}
bptr += nlen;
}
}
}
}
*bptr = '\0';
/*
* Sigh. Somebody actually attempted to use freedesktop.org pkg-config's broken sysroot support,
* which was written by somebody who did not understand how sysroots are supposed to work. This
* results in an incorrect path being built as the sysroot will be prepended twice, once explicitly,
* and once by variable expansion (the pkgconf approach). We could simply make ${pc_sysrootdir} blank,
* but sometimes it is necessary to know the explicit sysroot path for other reasons, so we can't really
* do that.
*
* As a result, we check to see if ${pc_sysrootdir} is prepended as a duplicate, and if so, remove the
* prepend. This allows us to handle both our approach and the broken freedesktop.org implementation's
* approach. Because a path can be shorter than ${pc_sysrootdir}, we do some checks first to ensure it's
* safe to skip ahead in the string to scan for our sysroot dir.
*
* Finally, we call pkgconf_path_relocate() to clean the path of spurious elements.
*
* New in 1.9: Only attempt to rewrite the sysroot if we are not processing an uninstalled package.
*/
if (should_rewrite_sysroot(client, vars, buf, flags))
{
char cleanpath[PKGCONF_ITEM_SIZE];
const char *sysroot_dir = find_sysroot(client, vars);
pkgconf_strlcpy(cleanpath, buf + strlen(sysroot_dir), sizeof cleanpath);
pkgconf_path_relocate(cleanpath, sizeof cleanpath);
return strdup(cleanpath);
}
return strdup(buf);
}
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_free_entry(pkgconf_tuple_t *tuple, pkgconf_list_t *list)
*
* Deletes a variable object, removing it from any variable lists and releasing any memory associated
* with it.
*
* :param pkgconf_tuple_t* tuple: The variable object to release.
* :param pkgconf_list_t* list: The variable list the variable object is attached to.
* :return: nothing
*/
void
pkgconf_tuple_free_entry(pkgconf_tuple_t *tuple, pkgconf_list_t *list)
{
pkgconf_node_delete(&tuple->iter, list);
free(tuple->key);
free(tuple->value);
free(tuple);
}
/*
* !doc
*
* .. c:function:: void pkgconf_tuple_free(pkgconf_list_t *list)
*
* Deletes a variable list and any variables attached to it.
*
* :param pkgconf_list_t* list: The variable list to delete.
* :return: nothing
*/
void
pkgconf_tuple_free(pkgconf_list_t *list)
{
pkgconf_node_t *node, *next;
PKGCONF_FOREACH_LIST_ENTRY_SAFE(list->head, next, node)
pkgconf_tuple_free_entry(node->data, list);
pkgconf_list_zero(list);
}