/* * deps.c * * Copyright (c) 2006-2013 Pacman Development Team <pacman-dev@archlinux.org> * Copyright (c) 2002-2006 by Judd Vinet <jvinet@zeroflux.org> * Copyright (c) 2005 by Aurelien Foret <orelien@chez.com> * Copyright (c) 2005, 2006 by Miklos Vajna <vmiklos@frugalware.org> * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ #include <stdlib.h> #include <stdio.h> #include <string.h> /* libalpm */ #include "deps.h" #include "alpm_list.h" #include "util.h" #include "log.h" #include "graph.h" #include "package.h" #include "db.h" #include "handle.h" #include "trans.h" void _alpm_dep_free(alpm_depend_t *dep) { FREE(dep->name); FREE(dep->version); FREE(dep->desc); FREE(dep); } static alpm_depmissing_t *depmiss_new(const char *target, alpm_depend_t *dep, const char *causingpkg) { alpm_depmissing_t *miss; MALLOC(miss, sizeof(alpm_depmissing_t), return NULL); STRDUP(miss->target, target, return NULL); miss->depend = _alpm_dep_dup(dep); STRDUP(miss->causingpkg, causingpkg, return NULL); return miss; } void _alpm_depmiss_free(alpm_depmissing_t *miss) { _alpm_dep_free(miss->depend); FREE(miss->target); FREE(miss->causingpkg); FREE(miss); } /* Does pkg1 depend on pkg2, ie. does pkg2 satisfy a dependency of pkg1? */ static int _alpm_dep_edge(alpm_pkg_t *pkg1, alpm_pkg_t *pkg2) { alpm_list_t *i; for(i = alpm_pkg_get_depends(pkg1); i; i = i->next) { if(_alpm_depcmp(pkg2, i->data)) { return 1; } } return 0; } /* Convert a list of alpm_pkg_t * to a graph structure, * with a edge for each dependency. * Returns a list of vertices (one vertex = one package) * (used by alpm_sortbydeps) */ static alpm_list_t *dep_graph_init(alpm_list_t *targets) { alpm_list_t *i, *j; alpm_list_t *vertices = NULL; /* We create the vertices */ for(i = targets; i; i = i->next) { alpm_graph_t *vertex = _alpm_graph_new(); vertex->data = (void *)i->data; vertices = alpm_list_add(vertices, vertex); } /* We compute the edges */ for(i = vertices; i; i = i->next) { alpm_graph_t *vertex_i = i->data; alpm_pkg_t *p_i = vertex_i->data; /* TODO this should be somehow combined with alpm_checkdeps */ for(j = vertices; j; j = j->next) { alpm_graph_t *vertex_j = j->data; alpm_pkg_t *p_j = vertex_j->data; if(_alpm_dep_edge(p_i, p_j)) { vertex_i->children = alpm_list_add(vertex_i->children, vertex_j); } } vertex_i->childptr = vertex_i->children; } return vertices; } /* Re-order a list of target packages with respect to their dependencies. * * Example (reverse == 0): * A depends on C * B depends on A * Target order is A,B,C,D * * Should be re-ordered to C,A,B,D * * if reverse is > 0, the dependency order will be reversed. * * This function returns the new alpm_list_t* target list. * */ alpm_list_t *_alpm_sortbydeps(alpm_handle_t *handle, alpm_list_t *targets, int reverse) { alpm_list_t *newtargs = NULL; alpm_list_t *vertices = NULL; alpm_list_t *vptr; alpm_graph_t *vertex; if(targets == NULL) { return NULL; } _alpm_log(handle, ALPM_LOG_DEBUG, "started sorting dependencies\n"); vertices = dep_graph_init(targets); vptr = vertices; vertex = vertices->data; while(vptr) { /* mark that we touched the vertex */ vertex->state = -1; int found = 0; while(vertex->childptr && !found) { alpm_graph_t *nextchild = vertex->childptr->data; vertex->childptr = vertex->childptr->next; if(nextchild->state == 0) { found = 1; nextchild->parent = vertex; vertex = nextchild; } else if(nextchild->state == -1) { alpm_pkg_t *vertexpkg = vertex->data; alpm_pkg_t *childpkg = nextchild->data; _alpm_log(handle, ALPM_LOG_WARNING, _("dependency cycle detected:\n")); if(reverse) { _alpm_log(handle, ALPM_LOG_WARNING, _("%s will be removed after its %s dependency\n"), vertexpkg->name, childpkg->name); } else { _alpm_log(handle, ALPM_LOG_WARNING, _("%s will be installed before its %s dependency\n"), vertexpkg->name, childpkg->name); } } } if(!found) { newtargs = alpm_list_add(newtargs, vertex->data); /* mark that we've left this vertex */ vertex->state = 1; vertex = vertex->parent; if(!vertex) { vptr = vptr->next; while(vptr) { vertex = vptr->data; if(vertex->state == 0) break; vptr = vptr->next; } } } } _alpm_log(handle, ALPM_LOG_DEBUG, "sorting dependencies finished\n"); if(reverse) { /* reverse the order */ alpm_list_t *tmptargs = alpm_list_reverse(newtargs); /* free the old one */ alpm_list_free(newtargs); newtargs = tmptargs; } alpm_list_free_inner(vertices, _alpm_graph_free); alpm_list_free(vertices); return newtargs; } static int no_dep_version(alpm_handle_t *handle) { if(!handle->trans) { return 0; } return (handle->trans->flags & ALPM_TRANS_FLAG_NODEPVERSION); } static alpm_depend_t *filtered_depend(alpm_depend_t *dep, int nodepversion) { if(nodepversion) { alpm_depend_t *newdep = _alpm_dep_dup(dep); ASSERT(newdep, return dep); newdep->mod = ALPM_DEP_MOD_ANY; dep = newdep; } return dep; } static void release_filtered_depend(alpm_depend_t *dep, int nodepversion) { if(nodepversion) { free(dep); } } static alpm_pkg_t *find_dep_satisfier(alpm_list_t *pkgs, alpm_depend_t *dep) { alpm_list_t *i; for(i = pkgs; i; i = i->next) { alpm_pkg_t *pkg = i->data; if(_alpm_depcmp(pkg, dep)) { return pkg; } } return NULL; } /** Find a package satisfying a specified dependency. * The dependency can include versions with depmod operators. * @param pkgs an alpm_list_t* of alpm_pkg_t where the satisfier will be searched * @param depstring package or provision name, versioned or not * @return a alpm_pkg_t* satisfying depstring */ alpm_pkg_t SYMEXPORT *alpm_find_satisfier(alpm_list_t *pkgs, const char *depstring) { alpm_depend_t *dep = _alpm_splitdep(depstring); if(!dep) { return NULL; } alpm_pkg_t *pkg = find_dep_satisfier(pkgs, dep); _alpm_dep_free(dep); return pkg; } /** Checks dependencies and returns missing ones in a list. * Dependencies can include versions with depmod operators. * @param handle the context handle * @param pkglist the list of local packages * @param remove an alpm_list_t* of packages to be removed * @param upgrade an alpm_list_t* of packages to be upgraded (remove-then-upgrade) * @param reversedeps handles the backward dependencies * @return an alpm_list_t* of alpm_depmissing_t pointers. */ alpm_list_t SYMEXPORT *alpm_checkdeps(alpm_handle_t *handle, alpm_list_t *pkglist, alpm_list_t *rem, alpm_list_t *upgrade, int reversedeps) { alpm_list_t *i, *j; alpm_list_t *dblist = NULL, *modified = NULL; alpm_list_t *baddeps = NULL; int nodepversion; CHECK_HANDLE(handle, return NULL); for(i = pkglist; i; i = i->next) { alpm_pkg_t *pkg = i->data; if(alpm_pkg_find(rem, pkg->name) || alpm_pkg_find(upgrade, pkg->name)) { modified = alpm_list_add(modified, pkg); } else { dblist = alpm_list_add(dblist, pkg); } } nodepversion = no_dep_version(handle); /* look for unsatisfied dependencies of the upgrade list */ for(i = upgrade; i; i = i->next) { alpm_pkg_t *tp = i->data; _alpm_log(handle, ALPM_LOG_DEBUG, "checkdeps: package %s-%s\n", tp->name, tp->version); for(j = alpm_pkg_get_depends(tp); j; j = j->next) { alpm_depend_t *depend = j->data; depend = filtered_depend(depend, nodepversion); /* 1. we check the upgrade list */ /* 2. we check database for untouched satisfying packages */ if(!find_dep_satisfier(upgrade, depend) && !find_dep_satisfier(dblist, depend)) { /* Unsatisfied dependency in the upgrade list */ alpm_depmissing_t *miss; char *missdepstring = alpm_dep_compute_string(depend); _alpm_log(handle, ALPM_LOG_DEBUG, "checkdeps: missing dependency '%s' for package '%s'\n", missdepstring, tp->name); free(missdepstring); miss = depmiss_new(tp->name, depend, NULL); baddeps = alpm_list_add(baddeps, miss); } release_filtered_depend(depend, nodepversion); } } if(reversedeps) { /* reversedeps handles the backwards dependencies, ie, * the packages listed in the requiredby field. */ for(i = dblist; i; i = i->next) { alpm_pkg_t *lp = i->data; for(j = alpm_pkg_get_depends(lp); j; j = j->next) { alpm_depend_t *depend = j->data; depend = filtered_depend(depend, nodepversion); alpm_pkg_t *causingpkg = find_dep_satisfier(modified, depend); /* we won't break this depend, if it is already broken, we ignore it */ /* 1. check upgrade list for satisfiers */ /* 2. check dblist for satisfiers */ if(causingpkg && !find_dep_satisfier(upgrade, depend) && !find_dep_satisfier(dblist, depend)) { alpm_depmissing_t *miss; char *missdepstring = alpm_dep_compute_string(depend); _alpm_log(handle, ALPM_LOG_DEBUG, "checkdeps: transaction would break '%s' dependency of '%s'\n", missdepstring, lp->name); free(missdepstring); miss = depmiss_new(lp->name, depend, causingpkg->name); baddeps = alpm_list_add(baddeps, miss); } release_filtered_depend(depend, nodepversion); } } } alpm_list_free(modified); alpm_list_free(dblist); return baddeps; } static int dep_vercmp(const char *version1, alpm_depmod_t mod, const char *version2) { int equal = 0; if(mod == ALPM_DEP_MOD_ANY) { equal = 1; } else { int cmp = alpm_pkg_vercmp(version1, version2); switch(mod) { case ALPM_DEP_MOD_EQ: equal = (cmp == 0); break; case ALPM_DEP_MOD_GE: equal = (cmp >= 0); break; case ALPM_DEP_MOD_LE: equal = (cmp <= 0); break; case ALPM_DEP_MOD_LT: equal = (cmp < 0); break; case ALPM_DEP_MOD_GT: equal = (cmp > 0); break; default: equal = 1; break; } } return equal; } int _alpm_depcmp_literal(alpm_pkg_t *pkg, alpm_depend_t *dep) { if(pkg->name_hash != dep->name_hash || strcmp(pkg->name, dep->name) != 0) { /* skip more expensive checks */ return 0; } return dep_vercmp(pkg->version, dep->mod, dep->version); } int _alpm_depcmp(alpm_pkg_t *pkg, alpm_depend_t *dep) { alpm_list_t *i; int satisfy = _alpm_depcmp_literal(pkg, dep); if(satisfy) { return satisfy; } /* check provisions, name and version if available */ for(i = alpm_pkg_get_provides(pkg); i && !satisfy; i = i->next) { alpm_depend_t *provision = i->data; if(dep->mod == ALPM_DEP_MOD_ANY) { /* any version will satisfy the requirement */ satisfy = (provision->name_hash == dep->name_hash && strcmp(provision->name, dep->name) == 0); } else if(provision->mod == ALPM_DEP_MOD_EQ) { /* provision specifies a version, so try it out */ satisfy = (provision->name_hash == dep->name_hash && strcmp(provision->name, dep->name) == 0 && dep_vercmp(provision->version, dep->mod, dep->version)); } } return satisfy; } alpm_depend_t *_alpm_splitdep(const char *depstring) { alpm_depend_t *depend; const char *ptr, *version, *desc; size_t deplen; if(depstring == NULL) { return NULL; } MALLOC(depend, sizeof(alpm_depend_t), return NULL); /* Note the extra space in ": " to avoid matching the epoch */ if((desc = strstr(depstring, ": ")) != NULL) { STRDUP(depend->desc, desc + 2, return NULL); deplen = desc - depstring; } else { /* no description- point desc at NULL at end of string for later use */ depend->desc = NULL; deplen = strlen(depstring); desc = depstring + deplen; } /* Find a version comparator if one exists. If it does, set the type and * increment the ptr accordingly so we can copy the right strings. */ if((ptr = memchr(depstring, '<', deplen))) { if(ptr[1] == '=') { depend->mod = ALPM_DEP_MOD_LE; version = ptr + 2; } else { depend->mod = ALPM_DEP_MOD_LT; version = ptr + 1; } } else if((ptr = memchr(depstring, '>', deplen))) { if(ptr[1] == '=') { depend->mod = ALPM_DEP_MOD_GE; version = ptr + 2; } else { depend->mod = ALPM_DEP_MOD_GT; version = ptr + 1; } } else if((ptr = memchr(depstring, '=', deplen))) { /* Note: we must do =,<,> checks after <=, >= checks */ depend->mod = ALPM_DEP_MOD_EQ; version = ptr + 1; } else { /* no version specified, set ptr to end of string and version to NULL */ ptr = depstring + deplen; depend->mod = ALPM_DEP_MOD_ANY; depend->version = NULL; version = NULL; } /* copy the right parts to the right places */ STRNDUP(depend->name, depstring, ptr - depstring, return NULL); depend->name_hash = _alpm_hash_sdbm(depend->name); if(version) { STRNDUP(depend->version, version, desc - version, return NULL); } return depend; } alpm_depend_t *_alpm_dep_dup(const alpm_depend_t *dep) { alpm_depend_t *newdep; CALLOC(newdep, 1, sizeof(alpm_depend_t), return NULL); STRDUP(newdep->name, dep->name, return NULL); STRDUP(newdep->version, dep->version, return NULL); STRDUP(newdep->desc, dep->desc, return NULL); newdep->name_hash = dep->name_hash; newdep->mod = dep->mod; return newdep; } /* These parameters are messy. We check if this package, given a list of * targets and a db is safe to remove. We do NOT remove it if it is in the * target list, or if if the package was explictly installed and * include_explicit == 0 */ static int can_remove_package(alpm_db_t *db, alpm_pkg_t *pkg, alpm_list_t *targets, int include_explicit) { alpm_list_t *i; if(alpm_pkg_find(targets, pkg->name)) { return 0; } if(!include_explicit) { /* see if it was explicitly installed */ if(alpm_pkg_get_reason(pkg) == ALPM_PKG_REASON_EXPLICIT) { _alpm_log(db->handle, ALPM_LOG_DEBUG, "excluding %s -- explicitly installed\n", pkg->name); return 0; } } /* TODO: checkdeps could be used here, it handles multiple providers * better, but that also makes it slower. * Also this would require to first add the package to the targets list, * then call checkdeps with it, then remove the package from the targets list * if checkdeps detected it would break something */ /* see if other packages need it */ for(i = _alpm_db_get_pkgcache(db); i; i = i->next) { alpm_pkg_t *lpkg = i->data; if(_alpm_dep_edge(lpkg, pkg) && !alpm_pkg_find(targets, lpkg->name)) { return 0; } } /* it's ok to remove */ return 1; } /** * @brief Adds unneeded dependencies to an existing list of packages. * By unneeded, we mean dependencies that are only required by packages in the * target list, so they can be safely removed. * If the input list was topo sorted, the output list will be topo sorted too. * * @param db package database to do dependency tracing in * @param *targs pointer to a list of packages * @param include_explicit if 0, explicitly installed packages are not included * @return 0 on success, -1 on errors */ int _alpm_recursedeps(alpm_db_t *db, alpm_list_t *targs, int include_explicit) { alpm_list_t *i, *j; if(db == NULL || targs == NULL) { return -1; } for(i = targs; i; i = i->next) { alpm_pkg_t *pkg = i->data; for(j = _alpm_db_get_pkgcache(db); j; j = j->next) { alpm_pkg_t *deppkg = j->data; if(_alpm_dep_edge(pkg, deppkg) && can_remove_package(db, deppkg, targs, include_explicit)) { alpm_pkg_t *copy; _alpm_log(db->handle, ALPM_LOG_DEBUG, "adding '%s' to the targets\n", deppkg->name); /* add it to the target list */ if(_alpm_pkg_dup(deppkg, ©)) { return -1; } targs = alpm_list_add(targs, copy); } } } return 0; } /** * helper function for resolvedeps: search for dep satisfier in dbs * * @param handle the context handle * @param dep is the dependency to search for * @param dbs are the databases to search * @param excluding are the packages to exclude from the search * @param prompt if true, will cause an unresolvable dependency to issue an * interactive prompt asking whether the package should be removed from * the transaction or the transaction aborted; if false, simply returns * an error code without prompting * @return the resolved package **/ static alpm_pkg_t *resolvedep(alpm_handle_t *handle, alpm_depend_t *dep, alpm_list_t *dbs, alpm_list_t *excluding, int prompt) { alpm_list_t *i, *j; int ignored = 0; alpm_list_t *providers = NULL; int count; /* 1. literals */ for(i = dbs; i; i = i->next) { alpm_pkg_t *pkg = _alpm_db_get_pkgfromcache(i->data, dep->name); if(pkg && _alpm_depcmp_literal(pkg, dep) && !alpm_pkg_find(excluding, pkg->name)) { if(_alpm_pkg_should_ignore(handle, pkg)) { int install = 0; if(prompt) { QUESTION(handle, ALPM_QUESTION_INSTALL_IGNOREPKG, pkg, NULL, NULL, &install); } else { _alpm_log(handle, ALPM_LOG_WARNING, _("ignoring package %s-%s\n"), pkg->name, pkg->version); } if(!install) { ignored = 1; continue; } } return pkg; } } /* 2. satisfiers (skip literals here) */ for(i = dbs; i; i = i->next) { for(j = _alpm_db_get_pkgcache(i->data); j; j = j->next) { alpm_pkg_t *pkg = j->data; /* with hash != hash, we can even skip the strcmp() as we know they can't * possibly be the same string */ if(pkg->name_hash != dep->name_hash && _alpm_depcmp(pkg, dep) && !alpm_pkg_find(excluding, pkg->name)) { if(_alpm_pkg_should_ignore(handle, pkg)) { int install = 0; if(prompt) { QUESTION(handle, ALPM_QUESTION_INSTALL_IGNOREPKG, pkg, NULL, NULL, &install); } else { _alpm_log(handle, ALPM_LOG_WARNING, _("ignoring package %s-%s\n"), pkg->name, pkg->version); } if(!install) { ignored = 1; continue; } } _alpm_log(handle, ALPM_LOG_DEBUG, "provider found (%s provides %s)\n", pkg->name, dep->name); providers = alpm_list_add(providers, pkg); /* keep looking for other providers in the all dbs */ } } } /* first check if one provider is already installed locally */ for(i = providers; i; i = i->next) { alpm_pkg_t *pkg = i->data; if(_alpm_db_get_pkgfromcache(handle->db_local, pkg->name)) { alpm_list_free(providers); return pkg; } } count = alpm_list_count(providers); if(count >= 1) { /* default to first provider if there is no QUESTION callback */ int idx = 0; if(count > 1) { /* if there is more than one provider, we ask the user */ QUESTION(handle, ALPM_QUESTION_SELECT_PROVIDER, providers, dep, NULL, &idx); } if(idx >= 0 && idx < count) { alpm_list_t *nth = alpm_list_nth(providers, idx); alpm_pkg_t *pkg = nth->data; alpm_list_free(providers); return pkg; } alpm_list_free(providers); providers = NULL; } if(ignored) { /* resolvedeps will override these */ handle->pm_errno = ALPM_ERR_PKG_IGNORED; } else { handle->pm_errno = ALPM_ERR_PKG_NOT_FOUND; } return NULL; } /** Find a package satisfying a specified dependency. * First look for a literal, going through each db one by one. Then look for * providers. The first satisfier found is returned. * The dependency can include versions with depmod operators. * @param handle the context handle * @param dbs an alpm_list_t* of alpm_db_t where the satisfier will be searched * @param depstring package or provision name, versioned or not * @return a alpm_pkg_t* satisfying depstring */ alpm_pkg_t SYMEXPORT *alpm_find_dbs_satisfier(alpm_handle_t *handle, alpm_list_t *dbs, const char *depstring) { alpm_depend_t *dep; alpm_pkg_t *pkg; CHECK_HANDLE(handle, return NULL); ASSERT(dbs, RET_ERR(handle, ALPM_ERR_WRONG_ARGS, NULL)); dep = _alpm_splitdep(depstring); ASSERT(dep, return NULL); pkg = resolvedep(handle, dep, dbs, NULL, 1); _alpm_dep_free(dep); return pkg; } /** * Computes resolvable dependencies for a given package and adds that package * and those resolvable dependencies to a list. * * @param handle the context handle * @param localpkgs is the list of local packages * @param pkg is the package to resolve * @param preferred packages to prefer when resolving * @param packages is a pointer to a list of packages which will be * searched first for any dependency packages needed to complete the * resolve, and to which will be added any [pkg] and all of its * dependencies not already on the list * @param remove is the set of packages which will be removed in this * transaction * @param data returns the dependency which could not be satisfied in the * event of an error * @return 0 on success, with [pkg] and all of its dependencies not already on * the [*packages] list added to that list, or -1 on failure due to an * unresolvable dependency, in which case the [*packages] list will be * unmodified by this function */ int _alpm_resolvedeps(alpm_handle_t *handle, alpm_list_t *localpkgs, alpm_pkg_t *pkg, alpm_list_t *preferred, alpm_list_t **packages, alpm_list_t *rem, alpm_list_t **data) { int ret = 0; alpm_list_t *j; alpm_list_t *targ; alpm_list_t *deps = NULL; alpm_list_t *packages_copy; if(alpm_pkg_find(*packages, pkg->name) != NULL) { return 0; } /* Create a copy of the packages list, so that it can be restored on error */ packages_copy = alpm_list_copy(*packages); /* [pkg] has not already been resolved into the packages list, so put it on that list */ *packages = alpm_list_add(*packages, pkg); _alpm_log(handle, ALPM_LOG_DEBUG, "started resolving dependencies\n"); targ = alpm_list_add(NULL, pkg); deps = alpm_checkdeps(handle, localpkgs, rem, targ, 0); alpm_list_free(targ); targ = NULL; for(j = deps; j; j = j->next) { alpm_depmissing_t *miss = j->data; alpm_depend_t *missdep = miss->depend; /* check if one of the packages in the [*packages] list already satisfies * this dependency */ if(find_dep_satisfier(*packages, missdep)) { _alpm_depmiss_free(miss); continue; } /* check if one of the packages in the [preferred] list already satisfies * this dependency */ alpm_pkg_t *spkg = find_dep_satisfier(preferred, missdep); if(!spkg) { /* find a satisfier package in the given repositories */ spkg = resolvedep(handle, missdep, handle->dbs_sync, *packages, 0); } if(spkg && _alpm_resolvedeps(handle, localpkgs, spkg, preferred, packages, rem, data) == 0) { _alpm_log(handle, ALPM_LOG_DEBUG, "pulling dependency %s (needed by %s)\n", spkg->name, pkg->name); _alpm_depmiss_free(miss); } else if(resolvedep(handle, missdep, (targ = alpm_list_add(NULL, handle->db_local)), rem, 0)) { _alpm_depmiss_free(miss); } else { handle->pm_errno = ALPM_ERR_UNSATISFIED_DEPS; char *missdepstring = alpm_dep_compute_string(missdep); _alpm_log(handle, ALPM_LOG_WARNING, _("cannot resolve \"%s\", a dependency of \"%s\"\n"), missdepstring, pkg->name); free(missdepstring); if(data) { *data = alpm_list_add(*data, miss); } ret = -1; } } alpm_list_free(targ); alpm_list_free(deps); if(ret != 0) { alpm_list_free(*packages); *packages = packages_copy; } else { alpm_list_free(packages_copy); } _alpm_log(handle, ALPM_LOG_DEBUG, "finished resolving dependencies\n"); return ret; } /** Reverse of splitdep; make a dep string from a alpm_depend_t struct. * The string must be freed! * @param dep the depend to turn into a string * @return a string-formatted dependency with operator if necessary */ char SYMEXPORT *alpm_dep_compute_string(const alpm_depend_t *dep) { const char *name, *opr, *ver, *desc_delim, *desc; char *str; size_t len; ASSERT(dep != NULL, return NULL); if(dep->name) { name = dep->name; } else { name = ""; } switch(dep->mod) { case ALPM_DEP_MOD_ANY: opr = ""; break; case ALPM_DEP_MOD_GE: opr = ">="; break; case ALPM_DEP_MOD_LE: opr = "<="; break; case ALPM_DEP_MOD_EQ: opr = "="; break; case ALPM_DEP_MOD_LT: opr = "<"; break; case ALPM_DEP_MOD_GT: opr = ">"; break; default: opr = ""; break; } if(dep->mod != ALPM_DEP_MOD_ANY && dep->version) { ver = dep->version; } else { ver = ""; } if(dep->desc) { desc_delim = ": "; desc = dep->desc; } else { desc_delim = ""; desc = ""; } /* we can always compute len and print the string like this because opr * and ver will be empty when ALPM_DEP_MOD_ANY is the depend type. the * reassignments above also ensure we do not do a strlen(NULL). */ len = strlen(name) + strlen(opr) + strlen(ver) + strlen(desc_delim) + strlen(desc) + 1; MALLOC(str, len, return NULL); snprintf(str, len, "%s%s%s%s%s", name, opr, ver, desc_delim, desc); return str; } /* vim: set ts=2 sw=2 noet: */