deps.c

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/*
 *  deps.c
 *
 *  Copyright (c) 2002-2007 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 "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

/* libalpm */
#include "deps.h"
#include "alpm_list.h"
#include "util.h"
#include "log.h"
#include "error.h"
#include "package.h"
#include "db.h"
#include "cache.h"
#include "handle.h"

void _alpm_dep_free(pmdepend_t *dep)
{
    FREE(dep->name);
    FREE(dep->version);
    FREE(dep);
}

static pmgraph_t *_alpm_graph_new(void)
{
    pmgraph_t *graph = NULL;

    ALPM_LOG_FUNC;

    MALLOC(graph, sizeof(pmgraph_t), RET_ERR(PM_ERR_MEMORY, NULL));

    if(graph) {
        graph->state = 0;
        graph->data = NULL;
        graph->parent = NULL;
        graph->children = NULL;
        graph->childptr = NULL;
    }
    return(graph);
}

static void _alpm_graph_free(void *data)
{
    pmgraph_t *graph = data;
    alpm_list_free(graph->children);
    free(graph);
}

pmdepmissing_t *_alpm_depmiss_new(const char *target, pmdepend_t *dep)
{
    pmdepmissing_t *miss;

    ALPM_LOG_FUNC;

    MALLOC(miss, sizeof(pmdepmissing_t), RET_ERR(PM_ERR_MEMORY, NULL));

    STRDUP(miss->target, target, RET_ERR(PM_ERR_MEMORY, NULL));
    miss->depend = _alpm_dep_dup(dep);

    return(miss);
}

void _alpm_depmiss_free(pmdepmissing_t *miss)
{
    _alpm_dep_free(miss->depend);
    FREE(miss->target);
    FREE(miss);
}

/* Convert a list of pmpkg_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 *_alpm_graph_init(alpm_list_t *targets)
{
    alpm_list_t *i, *j, *k;
    alpm_list_t *vertices = NULL;
    /* We create the vertices */
    for(i = targets; i; i = i->next) {
        pmgraph_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) {
        pmgraph_t *vertex_i = i->data;
        pmpkg_t *p_i = vertex_i->data;
        /* TODO this should be somehow combined with alpm_checkdeps */
        for(j = vertices; j; j = j->next) {
            pmgraph_t *vertex_j = j->data;
            pmpkg_t *p_j = vertex_j->data;
            int child = 0;
            for(k = alpm_pkg_get_depends(p_i); k && !child; k = k->next) {
                pmdepend_t *depend = k->data;
                child = alpm_depcmp(p_j, depend);
            }
            if(child) {
                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 (PM_TRANS_TYPE_ADD):
 *   A depends on C
 *   B depends on A
 *   Target order is A,B,C,D
 *
 *   Should be re-ordered to C,A,B,D
 *
 * mode should be either PM_TRANS_TYPE_ADD or PM_TRANS_TYPE_REMOVE.  This
 * affects the dependency order sortbydeps() will use.
 *
 * This function returns the new alpm_list_t* target list.
 *
 */
alpm_list_t *_alpm_sortbydeps(alpm_list_t *targets, pmtranstype_t mode)
{
    alpm_list_t *newtargs = NULL;
    alpm_list_t *vertices = NULL;
    alpm_list_t *vptr;
    pmgraph_t *vertex;

    ALPM_LOG_FUNC;

    if(targets == NULL) {
        return(NULL);
    }

    _alpm_log(PM_LOG_DEBUG, "started sorting dependencies\n");

    vertices = _alpm_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) {
            pmgraph_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) {
                pmpkg_t *vertexpkg = vertex->data;
                pmpkg_t *childpkg = nextchild->data;
                _alpm_log(PM_LOG_WARNING, _("dependency cycle detected:\n"));
                if(mode == PM_TRANS_TYPE_REMOVE) {
                    _alpm_log(PM_LOG_WARNING, _("%s will be removed after its %s dependency\n"), vertexpkg->name, childpkg->name);
                } else {
                    _alpm_log(PM_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(PM_LOG_DEBUG, "sorting dependencies finished\n");

    if(mode == PM_TRANS_TYPE_REMOVE) {
        /* we're removing packages, so 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);
}

/* Little helper function for alpm_list_find */
static int satisfycmp(const void *pkg, const void *depend)
{
    return(!alpm_depcmp((pmpkg_t*) pkg, (pmdepend_t*) depend));
}

/** Checks dependencies and returns missing ones in a list.
 * Dependencies can include versions with depmod operators.
 * @param db pointer to the local package database
 * @param reversedeps handles the backward dependencies
 * @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)
 * @return an alpm_list_t* of pmpkg_t* of missing_t pointers.
 */
alpm_list_t SYMEXPORT *alpm_checkdeps(pmdb_t *db, int reversedeps,
        alpm_list_t *remove, alpm_list_t *upgrade)
{
    alpm_list_t *i, *j;
    alpm_list_t *targets, *dblist = NULL, *modified = NULL;
    alpm_list_t *baddeps = NULL;
    pmdepmissing_t *miss = NULL;

    ALPM_LOG_FUNC;

    if(db == NULL) {
        return(NULL);
    }

    targets = alpm_list_join(alpm_list_copy(remove), alpm_list_copy(upgrade));
    for(i = _alpm_db_get_pkgcache(db); i; i = i->next) {
        void *pkg = i->data;
        if(alpm_list_find(targets, pkg, _alpm_pkg_cmp)) {
            modified = alpm_list_add(modified, pkg);
        } else {
            dblist = alpm_list_add(dblist, pkg);
        }
    }
    alpm_list_free(targets);

    /* look for unsatisfied dependencies of the upgrade list */
    for(i = upgrade; i; i = i->next) {
        pmpkg_t *tp = i->data;
        _alpm_log(PM_LOG_DEBUG, "checkdeps: package %s-%s\n",
                alpm_pkg_get_name(tp), alpm_pkg_get_version(tp));

        for(j = alpm_pkg_get_depends(tp); j; j = j->next) {
            pmdepend_t *depend = j->data;
            /* 1. we check the upgrade list */
            /* 2. we check database for untouched satisfying packages */
            if(!alpm_list_find(upgrade, depend, satisfycmp) &&
               !alpm_list_find(dblist, depend, satisfycmp)) {
                /* Unsatisfied dependency in the upgrade list */
                char *missdepstring = alpm_dep_get_string(depend);
                _alpm_log(PM_LOG_DEBUG, "checkdeps: missing dependency '%s' for package '%s'\n",
                        missdepstring, alpm_pkg_get_name(tp));
                free(missdepstring);
                miss = _alpm_depmiss_new(alpm_pkg_get_name(tp), depend);
                baddeps = alpm_list_add(baddeps, miss);
            }
        }
    }

    if(reversedeps) {
        /* reversedeps handles the backwards dependencies, ie,
         * the packages listed in the requiredby field. */
        for(i = dblist; i; i = i->next) {
            pmpkg_t *lp = i->data;
            for(j = alpm_pkg_get_depends(lp); j; j = j->next) {
                pmdepend_t *depend = j->data;
                /* 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(alpm_list_find(modified, depend, satisfycmp) &&
                   !alpm_list_find(upgrade, depend, satisfycmp) &&
                   !alpm_list_find(dblist, depend, satisfycmp)) {
                    char *missdepstring = alpm_dep_get_string(depend);
                    _alpm_log(PM_LOG_DEBUG, "checkdeps: transaction would break '%s' dependency of '%s'\n",
                            missdepstring, alpm_pkg_get_name(lp));
                    free(missdepstring);
                    miss = _alpm_depmiss_new(lp->name, depend);
                    baddeps = alpm_list_add(baddeps, miss);
                }
            }
        }
    }
    alpm_list_free(modified);
    alpm_list_free(dblist);

    return(baddeps);
}

static int dep_vercmp(const char *version1, pmdepmod_t mod,
        const char *version2)
{
    int equal = 0;

    if(mod == PM_DEP_MOD_ANY) {
        equal = 1;
    } else {
        int cmp = _alpm_versioncmp(version1, version2);
        switch(mod) {
            case PM_DEP_MOD_EQ: equal = (cmp == 0); break;
            case PM_DEP_MOD_GE: equal = (cmp >= 0); break;
            case PM_DEP_MOD_LE: equal = (cmp <= 0); break;
            case PM_DEP_MOD_LT: equal = (cmp < 0); break;
            case PM_DEP_MOD_GT: equal = (cmp > 0); break;
            default: equal = 1; break;
        }
    }
    return(equal);
}

int SYMEXPORT alpm_depcmp(pmpkg_t *pkg, pmdepend_t *dep)
{
    alpm_list_t *i;

    ALPM_LOG_FUNC;

    const char *pkgname = alpm_pkg_get_name(pkg);
    const char *pkgversion = alpm_pkg_get_version(pkg);
    int satisfy = 0;

    /* check (pkg->name, pkg->version) */
    satisfy = (strcmp(pkgname, dep->name) == 0
            && dep_vercmp(pkgversion, dep->mod, dep->version));

    /* check provisions, format : "name=version" */
    for(i = alpm_pkg_get_provides(pkg); i && !satisfy; i = i->next) {
        char *provname = strdup(i->data);
        char *provver = strchr(provname, '=');

        if(provver == NULL) { /* no provision version */
            satisfy = (dep->mod == PM_DEP_MOD_ANY
                    && strcmp(provname, dep->name) == 0);
        } else {
            /* replace the space with a NULL byte, and advance ptr the version */
            *provver = '\0';
            provver += 1;
            satisfy = (strcmp(provname, dep->name) == 0
                    && dep_vercmp(provver, dep->mod, dep->version));
        }
        free(provname);
    }

    return(satisfy);
}

pmdepend_t SYMEXPORT *alpm_splitdep(const char *depstring)
{
    pmdepend_t *depend;
    char *ptr = NULL;
    char *newstr = NULL;

    if(depstring == NULL) {
        return(NULL);
    }
    STRDUP(newstr, depstring, RET_ERR(PM_ERR_MEMORY, NULL));

    CALLOC(depend, sizeof(pmdepend_t), 1, RET_ERR(PM_ERR_MEMORY, NULL));

    /* 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 = strstr(newstr, ">="))) {
        depend->mod = PM_DEP_MOD_GE;
        *ptr = '\0';
        ptr += 2;
    } else if((ptr = strstr(newstr, "<="))) {
        depend->mod = PM_DEP_MOD_LE;
        *ptr = '\0';
        ptr += 2;
    } else if((ptr = strstr(newstr, "="))) { /* Note: we must do =,<,> checks after <=, >= checks */
        depend->mod = PM_DEP_MOD_EQ;
        *ptr = '\0';
        ptr += 1;
    } else if((ptr = strstr(newstr, "<"))) {
        depend->mod = PM_DEP_MOD_LT;
        *ptr = '\0';
        ptr += 1;
    } else if((ptr = strstr(newstr, ">"))) {
        depend->mod = PM_DEP_MOD_GT;
        *ptr = '\0';
        ptr += 1;
    } else {
        /* no version specified - copy the name and return it */
        depend->mod = PM_DEP_MOD_ANY;
        STRDUP(depend->name, newstr, RET_ERR(PM_ERR_MEMORY, NULL));
        depend->version = NULL;
        free(newstr);
        return(depend);
    }

    /* if we get here, we have a version comparator, copy the right parts
     * to the right places */
    STRDUP(depend->name, newstr, RET_ERR(PM_ERR_MEMORY, NULL));
    STRDUP(depend->version, ptr, RET_ERR(PM_ERR_MEMORY, NULL));
    free(newstr);

    return(depend);
}

pmdepend_t *_alpm_dep_dup(const pmdepend_t *dep)
{
    pmdepend_t *newdep;
    CALLOC(newdep, sizeof(pmdepend_t), 1, RET_ERR(PM_ERR_MEMORY, NULL));

    STRDUP(newdep->name, dep->name, RET_ERR(PM_ERR_MEMORY, NULL));
    STRDUP(newdep->version, dep->version, RET_ERR(PM_ERR_MEMORY, NULL));
    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(pmdb_t *db, pmpkg_t *pkg, alpm_list_t *targets,
        int include_explicit)
{
    alpm_list_t *i, *requiredby;

    if(_alpm_pkg_find(alpm_pkg_get_name(pkg), targets)) {
        return(0);
    }

    if(!include_explicit) {
        /* see if it was explicitly installed */
        if(alpm_pkg_get_reason(pkg) == PM_PKG_REASON_EXPLICIT) {
            _alpm_log(PM_LOG_DEBUG, "excluding %s -- explicitly installed\n",
                    alpm_pkg_get_name(pkg));
            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 */
    requiredby = alpm_pkg_compute_requiredby(pkg);
    for(i = requiredby; i; i = i->next) {
        pmpkg_t *reqpkg = _alpm_db_get_pkgfromcache(db, i->data);
        if(reqpkg && !_alpm_pkg_find(alpm_pkg_get_name(reqpkg), targets)) {
            FREELIST(requiredby);
            return(0);
        }
    }
    FREELIST(requiredby);

    /* 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
 */
void _alpm_recursedeps(pmdb_t *db, alpm_list_t *targs, int include_explicit)
{
    alpm_list_t *i, *j, *k;

    ALPM_LOG_FUNC;

    if(db == NULL || targs == NULL) {
        return;
    }

    for(i = targs; i; i = i->next) {
        pmpkg_t *pkg = i->data;
        for(j = alpm_pkg_get_depends(pkg); j; j = j->next) {
            pmdepend_t *depend = j->data;

            for(k = _alpm_db_get_pkgcache(db); k; k = k->next) {
                pmpkg_t *deppkg = k->data;
                if(alpm_depcmp(deppkg,depend)
                        && can_remove_package(db, deppkg, targs, include_explicit)) {
                    _alpm_log(PM_LOG_DEBUG, "adding '%s' to the targets\n",
                            alpm_pkg_get_name(deppkg));
                        /* add it to the target list */
                    targs = alpm_list_add(targs, _alpm_pkg_dup(deppkg));
                }
            }
        }
    }
}

/* populates *list with packages that need to be installed to satisfy all
 * dependencies (recursive) for syncpkg
 *
 * @param remove contains packages elected for removal
 * make sure **list is already initialized
 */
int _alpm_resolvedeps(pmdb_t *local, alpm_list_t *dbs_sync, pmpkg_t *syncpkg,
                      alpm_list_t **list, alpm_list_t *remove, pmtrans_t *trans, alpm_list_t **data)
{
    alpm_list_t *i, *j, *k;
    alpm_list_t *targ;
    alpm_list_t *deps = NULL;

    ALPM_LOG_FUNC;

    if(local == NULL || dbs_sync == NULL || syncpkg == NULL || list == NULL) {
        return(-1);
    }

    _alpm_log(PM_LOG_DEBUG, "started resolving dependencies\n");
    targ = alpm_list_add(NULL, syncpkg);
    deps = alpm_checkdeps(local, 0, remove, targ);
    alpm_list_free(targ);

    if(deps == NULL) {
        return(0);
    }

    for(i = deps; i; i = i->next) {
        int found = 0;
        pmdepmissing_t *miss = i->data;
        pmdepend_t *missdep = alpm_miss_get_dep(miss);
        pmpkg_t *sync = NULL;

        /* check if one of the packages in *list already satisfies this dependency */
        for(j = *list; j && !found; j = j->next) {
            pmpkg_t *sp = j->data;
            if(alpm_depcmp(sp, missdep)) {
                char *missdepstring = alpm_dep_get_string(missdep);
                _alpm_log(PM_LOG_DEBUG, "%s satisfies dependency %s -- skipping\n",
                          alpm_pkg_get_name(sp), missdepstring);
                free(missdepstring);
                found = 1;
            }
        }
        if(found) {
            continue;
        }

        /* find the package in one of the repositories */
        /* check literals */
        for(j = dbs_sync; j && !found; j = j->next) {
            sync = _alpm_db_get_pkgfromcache(j->data, missdep->name);
            if(!sync) {
                continue;
            }
            found = alpm_depcmp(sync, missdep) && !_alpm_pkg_find(alpm_pkg_get_name(sync), remove);
            if(!found) {
                continue;
            }
            /* If package is in the ignorepkg list, ask before we pull it */
            if(_alpm_pkg_should_ignore(sync)) {
                pmpkg_t *dummypkg = _alpm_pkg_new(miss->target, NULL);
                QUESTION(trans, PM_TRANS_CONV_INSTALL_IGNOREPKG, dummypkg, sync, NULL, &found);
                _alpm_pkg_free(dummypkg);
            }
        }
        /*TODO this autoresolves the first 'satisfier' package... we should fix this
         * somehow */
        /* check provides */
        /* we don't check literals again to avoid duplicated PM_TRANS_CONV_INSTALL_IGNOREPKG messages */
        for(j = dbs_sync; j && !found; j = j->next) {
            for(k = _alpm_db_get_pkgcache(j->data); k && !found; k = k->next) {
                sync = k->data;
                if(!sync) {
                    continue;
                }
                found = alpm_depcmp(sync, missdep) && strcmp(sync->name, missdep->name)
                    && !_alpm_pkg_find(alpm_pkg_get_name(sync), remove);
                if(!found) {
                    continue;
                }
                if(_alpm_pkg_should_ignore(sync)) {
                    pmpkg_t *dummypkg = _alpm_pkg_new(miss->target, NULL);
                    QUESTION(trans, PM_TRANS_CONV_INSTALL_IGNOREPKG, dummypkg, sync, NULL, &found);
                    _alpm_pkg_free(dummypkg);
                }
            }
        }

        if(!found) {
            char *missdepstring = alpm_dep_get_string(missdep);
            _alpm_log(PM_LOG_ERROR, _("cannot resolve \"%s\", a dependency of \"%s\"\n"),
                      missdepstring, miss->target);
            free(missdepstring);
            if(data) {
                MALLOC(miss, sizeof(pmdepmissing_t),/*nothing*/);
                if(!miss) {
                    pm_errno = PM_ERR_MEMORY;
                    FREELIST(*data);
                    goto error;
                }
                *miss = *(pmdepmissing_t *)i->data;
                *data = alpm_list_add(*data, miss);
            }
            pm_errno = PM_ERR_UNSATISFIED_DEPS;
            goto error;
        } else {
            _alpm_log(PM_LOG_DEBUG, "pulling dependency %s (needed by %s)\n",
                    alpm_pkg_get_name(sync), alpm_pkg_get_name(syncpkg));
            *list = alpm_list_add(*list, sync);
            if(_alpm_resolvedeps(local, dbs_sync, sync, list, remove, trans, data)) {
                goto error;
            }
        }
    }

    _alpm_log(PM_LOG_DEBUG, "finished resolving dependencies\n");

    alpm_list_free_inner(deps, (alpm_list_fn_free)_alpm_depmiss_free);
    alpm_list_free(deps);

    return(0);

error:
    FREELIST(deps);
    return(-1);
}

const char SYMEXPORT *alpm_miss_get_target(const pmdepmissing_t *miss)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(miss != NULL, return(NULL));

    return(miss->target);
}

pmdepend_t SYMEXPORT *alpm_miss_get_dep(pmdepmissing_t *miss)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(miss != NULL, return(NULL));

    return(miss->depend);
}

pmdepmod_t SYMEXPORT alpm_dep_get_mod(const pmdepend_t *dep)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(dep != NULL, return(-1));

    return(dep->mod);
}

const char SYMEXPORT *alpm_dep_get_name(const pmdepend_t *dep)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(dep != NULL, return(NULL));

    return(dep->name);
}

const char SYMEXPORT *alpm_dep_get_version(const pmdepend_t *dep)
{
    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(dep != NULL, return(NULL));

    return(dep->version);
}

/** Reverse of splitdep; make a dep string from a pmdepend_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_get_string(const pmdepend_t *dep)
{
    char *name, *opr, *ver, *str = NULL;
    size_t len;

    ALPM_LOG_FUNC;

    /* Sanity checks */
    ASSERT(dep != NULL, return(NULL));

    if(dep->name) {
        name = dep->name;
    } else {
        name = "";
    }

    switch(dep->mod) {
        case PM_DEP_MOD_ANY:
            opr = "";
            break;
        case PM_DEP_MOD_GE:
            opr = ">=";
            break;
        case PM_DEP_MOD_LE:
            opr = "<=";
            break;
        case PM_DEP_MOD_EQ:
            opr = "=";
            break;
        case PM_DEP_MOD_LT:
            opr = "<";
            break;
        case PM_DEP_MOD_GT:
            opr = ">";
            break;
        default:
            opr = "";
            break;
    }

    if(dep->version) {
        ver = dep->version;
    } else {
        ver = "";
    }

    /* we can always compute len and print the string like this because opr
     * and ver will be empty when PM_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) + 1;
    MALLOC(str, len, RET_ERR(PM_ERR_MEMORY, NULL));
    snprintf(str, len, "%s%s%s", name, opr, ver);

    return(str);
}
/* vim: set ts=2 sw=2 noet: */

---