Refactor solver dispatch and checkdata

13 files changed, 318 insertions, 246 deletions

diff --git a/src/nissy.c b/src/nissy.c
index acf6ebe..1f929c0 100644
--- a/src/nissy.c
+++ b/src/nissy.c
@@ -12,13 +12,10 @@
 #include "core/core.h"
 #include "solvers/solvers.h"
 
-long long parse_h48_solver(
-    const char *, uint8_t [static 1], uint8_t [static 1]);
 STATIC bool checkdata(const unsigned char *, const tableinfo_t [static 1]);
 STATIC bool distribution_equal(const uint64_t [static INFO_DISTRIBUTION_LEN],
     const uint64_t [static INFO_DISTRIBUTION_LEN], uint8_t);
 STATIC long long write_result(oriented_cube_t, char [static NISSY_SIZE_CUBE]);
-STATIC size_t my_strnlen(const char *, size_t); 
 STATIC long long nissy_dataid(const char *, char [static NISSY_SIZE_DATAID]);
 STATIC long long nissy_gendata_unsafe(
     const char *, unsigned long long, unsigned char *);
@@ -33,67 +30,20 @@ struct {
         GETCUBE_OPTIONS(NULL, NULL)
 };
 
-long long
-parse_h48_solver(const char *buf, uint8_t h[static 1], uint8_t k[static 1])
-{
-        const char *fullbuf = buf;
-
-        buf += 3;
-
-        if (*buf != 'h')
-                goto parse_h48_solver_error;
-        buf++;
-
-        *h = atoi(buf);
-
-        for ( ; *buf >= 0 + '0' && *buf <= 9 + '0'; buf++)
-                if (*buf == 0)
-                        goto parse_h48_solver_error;
-
-        if (*buf != 'k')
-                goto parse_h48_solver_error;
-        buf++;
-
-        *k = atoi(buf);
-
-        return *h < 12 && (*k == 2 || (*k == 4 && *h == 0)) ? 0 : 1;
-
-parse_h48_solver_error:
-        *h = 0;
-        *k = 0;
-        LOG("Error parsing H48 solver: must be in \"h48h*k*\" format,"
-            " but got %s\n", fullbuf);
-        return NISSY_ERROR_INVALID_SOLVER;
-}
-
 STATIC bool
 checkdata(const unsigned char *buf, const tableinfo_t info[static 1])
 {
         uint64_t distr[INFO_DISTRIBUTION_LEN];
 
-        if (my_strnlen(info->solver, INFO_SOLVER_STRLEN)
-            == INFO_SOLVER_STRLEN) {
-                LOG("[checkdata] Error reading table info\n");
-                return false;
-        } else if (!strncmp(info->solver, "cocsep", 6)) {
-                getdistribution_cocsep(
-                    (uint32_t *)((char *)buf + INFOSIZE), distr);
-        } else if (!strncmp(info->solver, "h48", 3)) {
-                getdistribution_h48(buf + INFOSIZE, distr,
-                    info->h48h, info->bits);
-        } else if (!strncmp(info->solver, "coordinate solver for ", 22)) {
-                getdistribution_coord(buf + INFOSIZE,
-                    info->solver + 22, distr);
-        } else if (!strncmp(info->solver, "eoesep data for h48", 19)) {
-                return true;
-        } else if (!strncmp(info->solver, "coord helper table for ", 23)) {
-                return true;
+        if (info->type == TABLETYPE_PRUNING) {
+                getdistribution(buf + INFOSIZE, distr, info);
+                LOG("\n[checkdata] Checking distribution for %s\n", info->solver);
+                return distribution_equal(info->distribution, distr, info->maxvalue);
         } else {
-                LOG("[checkdata] unknown solver %s\n", info->solver);
-                return false;
+                LOG("\n[checkdata] Skipping distribution check for "
+                    "special table %s\n", info->solver);
+                return true;
         }
-
-        return distribution_equal(info->distribution, distr, info->maxvalue);
 }
 
 STATIC bool
@@ -109,8 +59,12 @@ distribution_equal(
         for (i = 0, wrong = 0; i <= MIN(maxvalue, 20); i++) {
                 if (expected[i] != actual[i]) {
                         wrong++;
-                        LOG("Value %" PRIu8 ": expected %" PRIu64 ", found %"
-                            PRIu64 "\n", i, expected[i], actual[i]);
+                        LOG("[checkdata] Value for depth %" PRIu8
+                            ": expected %" PRIu64 ", found %" PRIu64 "\n",
+                            i, expected[i], actual[i]);
+                } else {
+                        LOG("[checkdata] Value for depth %" PRIu8
+                            " is correct (%" PRIu64 ")\n", i, actual[i]);
                 }
         }
 
@@ -130,18 +84,6 @@ write_result(oriented_cube_t cube, char result[static NISSY_SIZE_CUBE])
         return NISSY_OK;
 }
 
-STATIC size_t
-my_strnlen(const char *str, size_t maxlen)
-{
-        size_t i;
-
-        for (i = 0; i < maxlen; i++)
-                if (str[i] == '\0')
-                        return i;
-
-        return maxlen;
-}
-
 long long
 nissy_inverse(
         const char cube[static NISSY_SIZE_CUBE],
@@ -337,22 +279,15 @@ nissy_datainfo(
 STATIC long long
 nissy_dataid(const char *solver, char dataid[static NISSY_SIZE_DATAID])
 {
-        if (!strncmp(solver, "h48", 3)) {
-                uint8_t h, k;
-                long long err;
-                if ((err = parse_h48_solver(solver, &h, &k)) != NISSY_OK)
-                        return err;
-                /* TODO: also check that h and k are admissible */
-                else strcpy(dataid, solver);
-                return err;
-                /* TODO: do this when moved parser */
-                /* return dataid_h48(solver, dataid); */
-        } else if (!strncmp(solver, "coord_", 6)) {
-                return dataid_coord(solver+6, dataid);
-        } else {
-                LOG("[gendata] Unknown solver %s\n", solver);
+        solver_dispatch_t *dispatch;
+
+        dispatch = match_solver(solver);
+        if (dispatch == NULL) {
+                LOG("[dataid] Unknown solver %s\n", solver);
                 return NISSY_ERROR_INVALID_SOLVER;
         }
+
+        return dispatch->dataid(solver, dataid);
 }
 
 long long
@@ -386,8 +321,7 @@ nissy_gendata_unsafe(
         unsigned char *data
 )
 {
-        long long parse_ret;
-        gendata_h48_arg_t arg;
+        solver_dispatch_t *dispatch;
 
         if (solver == NULL) {
                 LOG("[gendata] Error: 'solver' argument is NULL\n");
@@ -399,20 +333,13 @@ nissy_gendata_unsafe(
                 return NISSY_ERROR_DATA;
         }
 
-        if (!strncmp(solver, "h48", 3)) {
-                arg.buf_size = data_size;
-                arg.buf = data;
-                parse_ret = parse_h48_solver(solver, &arg.h, &arg.k);
-                arg.maxdepth = 20;
-                if (parse_ret != NISSY_OK)
-                        return parse_ret;
-                return gendata_h48(&arg);
-        } else if (!strncmp(solver, "coord_", 6)) {
-                return gendata_coord_dispatch(solver+6, data);
-        } else {
+        dispatch = match_solver(solver);
+        if (dispatch == NULL) {
                 LOG("[gendata] Unknown solver %s\n", solver);
                 return NISSY_ERROR_INVALID_SOLVER;
         }
+
+        return dispatch->gendata(solver, data_size, data);
 }
 
 long long
@@ -466,9 +393,8 @@ nissy_solve(
 )
 {
         oriented_cube_t oc;
-        long long parse_ret;
-        uint8_t h, k;
         int t;
+        solver_dispatch_t *dispatch;
 
         if (solver == NULL) {
                 LOG("[solve] Error: 'solver' argument is NULL\n");
@@ -511,21 +437,14 @@ nissy_solve(
                 return NISSY_ERROR_DATA;
         }
 
-        if (!strncmp(solver, "h48", 3)) {
-                parse_ret = parse_h48_solver(solver, &h, &k);
-                if (parse_ret != NISSY_OK)
-                        return parse_ret;
-                return solve_h48(oc, minmoves, maxmoves, maxsols,
-                    optimal, t, data_size, data, sols_size, sols, stats,
-                    poll_status, poll_status_data);
-        } else if (!strncmp(solver, "coord_", 6)) {
-                return solve_coord_dispatch(oc, solver + 6, nissflag,
-                    minmoves, maxmoves, maxsols, optimal, t, data_size, data,
-                    sols_size, sols, poll_status, poll_status_data);
-        } else {
+        dispatch = match_solver(solver);
+        if (dispatch == NULL) {
                 LOG("[solve] Error: unknown solver '%s'\n", solver);
                 return NISSY_ERROR_INVALID_SOLVER;
         }
+        return dispatch->solve(oc, solver, nissflag, minmoves, maxmoves,
+            maxsols, optimal, t, data_size, data, sols_size, sols, stats,
+            poll_status, poll_status_data);
 }
 
 long long
diff --git a/src/solvers/coord/gendata.h b/src/solvers/coord/gendata.h
index 7a974f8..1b65f49 100644
--- a/src/solvers/coord/gendata.h
+++ b/src/solvers/coord/gendata.h
@@ -1,5 +1,6 @@
 STATIC size_t gendata_coord(const coord_t [static 1], unsigned char *);
-STATIC int64_t gendata_coord_dispatch(const char *, unsigned char *);
+STATIC long long gendata_coord_dispatch(const char *, unsigned long long,
+    unsigned char *);
 STATIC tableinfo_t genptable_coord(
     const coord_t [static 1], const unsigned char *, unsigned char *);
 STATIC bool switch_to_fromnew(uint64_t, uint64_t, uint64_t);
@@ -7,15 +8,17 @@ STATIC uint64_t genptable_coord_fillneighbors(const coord_t [static 1],
     const unsigned char *, uint64_t, uint8_t, unsigned char *);
 STATIC uint64_t genptable_coord_fillfromnew(const coord_t [static 1],
     const unsigned char *, uint64_t, uint8_t, unsigned char *);
-STATIC void getdistribution_coord(const unsigned char *, const char *,
-    uint64_t [static INFO_DISTRIBUTION_LEN]);
 STATIC uint8_t get_coord_pval(
     const coord_t [static 1], const unsigned char *, uint64_t);
 STATIC void set_coord_pval(
     const coord_t [static 1], unsigned char *, uint64_t, uint8_t);
 
-STATIC int64_t
-gendata_coord_dispatch(const char *coordstr, unsigned char *buf)
+STATIC long long
+gendata_coord_dispatch(
+        const char *coordstr,
+        unsigned long long bufsize,
+        unsigned char *buf
+)
 {
         coord_t *coord;
 
@@ -249,28 +252,6 @@ genptable_coord_fillfromnew(
         return tot;
 }
 
-STATIC void
-getdistribution_coord(
-        const unsigned char *table,
-        const char *coord,
-        uint64_t distr[static INFO_DISTRIBUTION_LEN]
-)
-{
-        uint8_t v;
-        uint64_t i;
-        coord_t *c;
-
-        memset(distr, 0, INFO_DISTRIBUTION_LEN * sizeof(uint64_t));
-
-        if((c = parse_coord(strlen(coord), coord)) == NULL)
-                return;
-
-        for (i = 0; i < c->max; i++) {
-                v = get_coord_pval(c, table, i);
-                distr[v]++;
-        }
-}
-
 STATIC uint8_t
 get_coord_pval(
         const coord_t coord[static 1],
diff --git a/src/solvers/coord/solve.h b/src/solvers/coord/solve.h
index 8eb3e9d..df0f6ff 100644
--- a/src/solvers/coord/solve.h
+++ b/src/solvers/coord/solve.h
@@ -13,11 +13,13 @@ typedef struct {
 } dfsarg_solve_coord_t;
 
 STATIC int64_t solve_coord(oriented_cube_t, coord_t [static 1], uint8_t,
-    uint8_t, uint8_t, uint8_t, uint64_t, uint8_t, uint8_t, uint64_t,
-    const unsigned char *, size_t n, char [n], int (*)(void *), void *);
-STATIC int64_t solve_coord_dispatch(oriented_cube_t, const char *, uint8_t,
-    uint8_t, uint8_t, uint64_t, uint8_t, uint8_t, uint64_t,
-    const unsigned char *, size_t n, char [n], int (*)(void *), void *);
+    uint8_t, uint8_t, uint8_t, uint64_t, uint8_t, uint8_t, uint64_t n,
+    const unsigned char [n], size_t m, char [m], int (*)(void *), void *);
+STATIC long long solve_coord_dispatch(oriented_cube_t, const char *, unsigned,
+    unsigned, unsigned, unsigned, unsigned, unsigned, unsigned long long n,
+    const unsigned char [n], unsigned m, char [m],
+    long long [static NISSY_SIZE_SOLVE_STATS],
+    int (*)(void *), void *);
 STATIC bool coord_solution_admissible(const dfsarg_solve_coord_t [static 1]);
 STATIC bool solve_coord_dfs_stop(const dfsarg_solve_coord_t [static 1]);
 STATIC bool coord_continue_onnormal(const dfsarg_solve_coord_t [static 1]);
@@ -198,20 +200,21 @@ solve_coord_dfs(dfsarg_solve_coord_t arg[static 1])
         return ret;
 }
 
-STATIC int64_t
+STATIC long long
 solve_coord_dispatch(
         oriented_cube_t oc,
         const char *coord_and_axis,
-        uint8_t nissflag,
-        uint8_t minmoves,
-        uint8_t maxmoves,
-        uint64_t maxsolutions,
-        uint8_t optimal,
-        uint8_t threads,
-        uint64_t data_size,
-        const unsigned char *data,
-        size_t solutions_size,
+        unsigned nissflag,
+        unsigned minmoves,
+        unsigned maxmoves,
+        unsigned maxsolutions,
+        unsigned optimal,
+        unsigned threads,
+        unsigned long long data_size,
+        const unsigned char data[data_size],
+        unsigned solutions_size,
         char sols[solutions_size],
+        long long stats[static NISSY_SIZE_SOLVE_STATS],
         int (*poll_status)(void *),
         void *poll_status_data
 )
@@ -250,7 +253,7 @@ solve_coord(
         uint8_t optimal,
         uint8_t threads,
         uint64_t data_size,
-        const unsigned char *data,
+        const unsigned char data[data_size],
         size_t solutions_size,
         char sols[solutions_size],
         int (*poll_status)(void *),
diff --git a/src/solvers/coord/utils.h b/src/solvers/coord/utils.h
index ef3f817..aa4d74c 100644
--- a/src/solvers/coord/utils.h
+++ b/src/solvers/coord/utils.h
@@ -2,7 +2,7 @@ STATIC coord_t *parse_coord(size_t n, const char [n]);
 STATIC uint8_t parse_axis(size_t n, const char [n]);
 STATIC void parse_coord_and_axis(
     size_t n, const char [n], coord_t **, uint8_t *);
-STATIC int64_t dataid_coord(const char *, char [static NISSY_SIZE_DATAID]);
+STATIC long long dataid_coord(const char *, char [static NISSY_SIZE_DATAID]);
 
 STATIC coord_t *
 parse_coord(size_t n, const char coord[n])
@@ -38,20 +38,22 @@ parse_coord_and_axis(
         uint8_t *axis
 )
 {
+        const char *s;
         size_t i;
 
+        s = str + 6;
         for (i = 0; i < n; i++)
-                if (str[i] == '_')
+                if (s[i] == '_')
                         break;
 
         if (coord != NULL)
-                *coord = parse_coord(i, str);
+                *coord = parse_coord(i, s);
 
         if (axis != NULL)
-                *axis = i == n ? UINT8_ERROR : parse_axis(n-i-1, str+i+1);
+                *axis = i == n ? UINT8_ERROR : parse_axis(n-i-1, s+i+1);
 }
 
-STATIC int64_t
+STATIC long long
 dataid_coord(const char *ca, char dataid[static NISSY_SIZE_DATAID])
 {
         coord_t *c;
diff --git a/src/solvers/dispatch.h b/src/solvers/dispatch.h
new file mode 100644
index 0000000..0cfbc3b
--- /dev/null
+++ b/src/solvers/dispatch.h
@@ -0,0 +1,49 @@
+typedef struct {
+        const char *prefix;
+        long long (*dataid)(const char *, char [static NISSY_SIZE_DATAID]);
+        long long (*gendata)(
+            const char *, unsigned long long, unsigned char *);
+        long long (*solve)(oriented_cube_t, const char *, unsigned, unsigned,
+            unsigned, unsigned, unsigned, unsigned, unsigned long long,
+            const unsigned char *, unsigned, char *,
+            long long [static NISSY_SIZE_SOLVE_STATS],
+            int (*)(void *), void *);
+} solver_dispatch_t;
+
+STATIC solver_dispatch_t *match_solver(const char *);
+
+solver_dispatch_t solver_dispatchers[] = {
+{
+        .prefix = "h48",
+        .dataid = dataid_h48,
+        .gendata = gendata_h48_dispatch,
+        .solve = solve_h48_dispatch,
+},
+{
+        .prefix = "coord_",
+        .dataid = dataid_coord,
+        .gendata = gendata_coord_dispatch,
+        .solve = solve_coord_dispatch,
+},
+{
+        .prefix = NULL
+}
+};
+
+STATIC solver_dispatch_t *
+match_solver(const char *name)
+{
+        const char *prefix;
+        int i;
+
+        if (name == NULL)
+                return NULL;
+
+        for (i = 0; solver_dispatchers[i].prefix != NULL; i++) {
+                prefix = solver_dispatchers[i].prefix;
+                if (!strncmp(name, prefix, strlen(prefix)))
+                        return &solver_dispatchers[i];
+        }
+
+        return NULL;
+}
diff --git a/src/solvers/distribution.h b/src/solvers/distribution.h
new file mode 100644
index 0000000..1a3719c
--- /dev/null
+++ b/src/solvers/distribution.h
@@ -0,0 +1,77 @@
+#define ENTRIES_PER_BYTE(k) (UINT64_C(8) / (uint64_t)(k))
+#define TABLE_SHIFT(i, k)   ((uint8_t)(k) * (uint8_t)((i) % ENTRIES_PER_BYTE(k)))
+#define TABLE_MASK(i, k)    ((UINT8_BIT(k) - UINT8_C(1)) << TABLE_SHIFT(i, k))
+
+typedef struct {
+        uint64_t min;
+        uint64_t max;
+        uint8_t bits;
+        uint64_t *distr;
+        const unsigned char *table;
+} getdistribution_data_t;
+
+STATIC void *getdistribution_runthread(void *);
+STATIC void getdistribution(const unsigned char *,
+    uint64_t [static INFO_DISTRIBUTION_LEN], const tableinfo_t [static 1]);
+
+STATIC void *
+getdistribution_runthread(void *arg)
+{
+        getdistribution_data_t *data = (getdistribution_data_t *)arg;
+        const unsigned char *table;
+        uint8_t j, k, m;
+        uint64_t i;
+
+        memset(data->distr, 0, INFO_DISTRIBUTION_LEN * sizeof(uint64_t));
+
+        k = data->bits;
+        table = data->table;
+        m = TABLE_MASK(0, k);
+        for (i = data->min; i < data->max; i++)
+                for (j = 0; j < ENTRIES_PER_BYTE(k); j++)
+                        data->distr[(table[i] & (m << (j*k))) >> (j*k)]++;
+
+        return NULL;
+}
+
+STATIC void
+getdistribution(
+        const unsigned char *table,
+        uint64_t distr[static INFO_DISTRIBUTION_LEN],
+        const tableinfo_t info[static 1]
+) {
+        getdistribution_data_t targ[THREADS];
+        pthread_t thread[THREADS];
+        uint8_t pval, k;
+        uint64_t local_distr[THREADS][INFO_DISTRIBUTION_LEN];
+        uint64_t i, j, nbytes, sz, epb;
+
+        k = info->bits;
+        epb = ENTRIES_PER_BYTE(k);
+        nbytes = info->entries / epb;
+        sz = nbytes / THREADS;
+        for (i = 0; i < THREADS; i++) {
+                targ[i] = (getdistribution_data_t) {
+                        .min = i * sz,
+                        .max = i == THREADS - 1 ? nbytes : (i+1) * sz,
+                        .bits = k,
+                        .distr = local_distr[i],
+                        .table = table,
+                };
+                pthread_create(&thread[i], NULL,
+                    getdistribution_runthread, &targ[i]);
+        }
+
+        for (i = 0; i < THREADS; i++)
+                pthread_join(thread[i], NULL);
+
+        memset(distr, 0, INFO_DISTRIBUTION_LEN * sizeof(uint64_t));
+        for (i = 0; i < THREADS; i++)
+                for (j = 0; j < INFO_DISTRIBUTION_LEN; j++)
+                        distr[j] += local_distr[i][j];
+
+        for (i = nbytes * epb; i < info->entries; i++) {
+                pval = (table[i/epb] & TABLE_MASK(i, k)) >> TABLE_SHIFT(i, k);
+                distr[pval]++;
+        }
+}
diff --git a/src/solvers/h48/gendata_cocsep.h b/src/solvers/h48/gendata_cocsep.h
index 2eac383..3117a8e 100644
--- a/src/solvers/h48/gendata_cocsep.h
+++ b/src/solvers/h48/gendata_cocsep.h
@@ -1,7 +1,5 @@
 STATIC size_t gendata_cocsep(unsigned char *, uint64_t *, cube_t *);
 STATIC uint32_t gendata_cocsep_dfs(cocsep_dfs_arg_t [static 1]);
-STATIC void getdistribution_cocsep(
-    const uint32_t [static COCSEP_TABLESIZE], uint64_t [static 21]);
 
 STATIC_INLINE bool gendata_cocsep_get_visited(
     const uint8_t [static COCSEP_VISITEDSIZE], int64_t);
@@ -136,20 +134,6 @@ gendata_cocsep_dfs(cocsep_dfs_arg_t arg[static 1])
         return cc;
 }
 
-STATIC void
-getdistribution_cocsep(
-    const uint32_t table[static COCSEP_TABLESIZE],
-    uint64_t distr[static 21]
-)
-{
-        size_t i;
-
-        memset(distr, 0, 21 * sizeof(uint64_t));
-
-        for (i = 0; i < COCSEP_TABLESIZE; i++)
-                distr[CBOUND(table[i])]++;
-}
-
 STATIC_INLINE bool
 gendata_cocsep_get_visited(
         const uint8_t a[static COCSEP_VISITEDSIZE],
diff --git a/src/solvers/h48/gendata_h48.h b/src/solvers/h48/gendata_h48.h
index c1a9ced..644ddc2 100644
--- a/src/solvers/h48/gendata_h48.h
+++ b/src/solvers/h48/gendata_h48.h
@@ -1,3 +1,5 @@
+STATIC long long gendata_h48_dispatch(
+    const char *, unsigned long long, unsigned char *);
 STATIC uint64_t gendata_h48short(gendata_h48short_arg_t [static 1]);
 STATIC int64_t gendata_h48(gendata_h48_arg_t [static 1]);
 STATIC void gendata_h48h0k4(gendata_h48_arg_t [static 1]);
@@ -12,9 +14,6 @@ STATIC_INLINE bool gendata_h48k2_dfs_stop(
     cube_t, int8_t, h48k2_dfs_arg_t [static 1]);
 STATIC void gendata_h48k2_dfs(h48k2_dfs_arg_t [static 1]);
 STATIC tableinfo_t makeinfo_h48k2(gendata_h48_arg_t [static 1]);
-STATIC void *getdistribution_h48_runthread(void *);
-STATIC void getdistribution_h48(const unsigned char *,
-    uint64_t [static INFO_DISTRIBUTION_LEN], uint8_t, uint8_t);
 
 STATIC const uint32_t *get_cocsepdata_constptr(const unsigned char *);
 STATIC const unsigned char *get_h48data_constptr(const unsigned char *);
@@ -28,6 +27,27 @@ STATIC_INLINE void set_h48_pval_atomic(
 
 size_t gendata_h48_derive(uint8_t, const unsigned char *, unsigned char *);
 
+STATIC long long
+gendata_h48_dispatch(
+        const char *solver,
+        unsigned long long data_size,
+        unsigned char *data
+)
+{
+        long long err;
+        gendata_h48_arg_t arg;
+
+        err = parse_h48_hk(solver, &arg.h, &arg.k);
+        if (err != NISSY_OK)
+                return err;
+
+        arg.buf_size = data_size;
+        arg.buf = data;
+        arg.maxdepth = 20;
+
+        return gendata_h48(&arg);
+}
+
 STATIC uint64_t
 gendata_h48short(gendata_h48short_arg_t arg[static 1])
 {
@@ -649,64 +669,6 @@ makeinfo_h48k2(gendata_h48_arg_t arg[static 1])
         return info;
 }
 
-STATIC void *
-getdistribution_h48_runthread(void *arg)
-{
-        getdistribution_h48_data_t *data = (getdistribution_h48_data_t *)arg;
-        const unsigned char *table;
-        uint8_t j, k, m;
-        int64_t i;
-
-        memset(data->distr, 0, INFO_DISTRIBUTION_LEN * sizeof(uint64_t));
-
-        k = data->k;
-        table = data->table;
-        m = H48_MASK(0, k);
-        for (i = data->min; i < data->max; i++)
-                for (j = 0; j < H48_DIV(k); j++)
-                        data->distr[(table[i] & (m << (j*k))) >> (j*k)]++;
-
-        return NULL;
-}
-
-STATIC void
-getdistribution_h48(
-        const unsigned char *table,
-        uint64_t distr[static INFO_DISTRIBUTION_LEN],
-        uint8_t h,
-        uint8_t k
-) {
-        getdistribution_h48_data_t targ[THREADS];
-        pthread_t thread[THREADS];
-        uint64_t local_distr[THREADS][INFO_DISTRIBUTION_LEN];
-        int64_t i, j, nbytes, sz;
-
-        nbytes = H48_COORDMAX(h) / H48_DIV(k);
-        sz = nbytes / THREADS;
-        for (i = 0; i < THREADS; i++) {
-                targ[i] = (getdistribution_h48_data_t) {
-                        .min = i * sz,
-                        .max = i == THREADS - 1 ? nbytes : (i+1) * sz,
-                        .k = k,
-                        .distr = local_distr[i],
-                        .table = table,
-                };
-                pthread_create(&thread[i], NULL,
-                    getdistribution_h48_runthread, &targ[i]);
-        }
-
-        for (i = 0; i < THREADS; i++)
-                pthread_join(thread[i], NULL);
-
-        memset(distr, 0, INFO_DISTRIBUTION_LEN * sizeof(uint64_t));
-        for (i = 0; i < THREADS; i++)
-                for (j = 0; j < INFO_DISTRIBUTION_LEN; j++)
-                        distr[j] += local_distr[i][j];
-
-        for (i = nbytes * H48_DIV(k); i < H48_COORDMAX(h); i++)
-                distr[get_h48_pval(table, i, k)]++;
-}
-
 STATIC const uint32_t *
 get_cocsepdata_constptr(const unsigned char *data)
 {
@@ -821,7 +783,7 @@ gendata_h48_derive(uint8_t h, const unsigned char *fulltable, unsigned char *buf
                     h48derive, j, arg.k, MIN(val_full, val_derive));
         }
 
-        getdistribution_h48(h48derive, arg.info.distribution, h, arg.k);
+        getdistribution(h48derive, arg.info.distribution, &arg.info);
 
         bufsize = arg.buf_size - COCSEP_FULLSIZE - INFOSIZE;
         if (writetableinfo(&arg.info, bufsize, (unsigned char *)arg.h48buf)
diff --git a/src/solvers/h48/gendata_types_macros.h b/src/solvers/h48/gendata_types_macros.h
index c4b1b5a..b0592c2 100644
--- a/src/solvers/h48/gendata_types_macros.h
+++ b/src/solvers/h48/gendata_types_macros.h
@@ -121,11 +121,3 @@ typedef struct {
         _Atomic unsigned char *table_atomic;
         pthread_mutex_t **table_mutex;
 } gendata_h48_mark_t;
-
-typedef struct {
-        int64_t min;
-        int64_t max;
-        uint8_t k;
-        uint64_t *distr;
-        const unsigned char *table;
-} getdistribution_h48_data_t;
diff --git a/src/solvers/h48/h48.h b/src/solvers/h48/h48.h
index 0cfa773..79d2583 100644
--- a/src/solvers/h48/h48.h
+++ b/src/solvers/h48/h48.h
@@ -1,3 +1,4 @@
+#include "utils.h"
 #include "coordinate_types_macros.h"
 #include "map_types_macros.h"
 #include "gendata_types_macros.h"
diff --git a/src/solvers/h48/solve.h b/src/solvers/h48/solve.h
index f2967ed..2818c09 100644
--- a/src/solvers/h48/solve.h
+++ b/src/solvers/h48/solve.h
@@ -50,6 +50,10 @@ typedef struct {
         int8_t *shortest_sol;
 } dfsarg_solve_h48_maketasks_t;
 
+STATIC long long solve_h48_dispatch(oriented_cube_t, const char *, unsigned,
+    unsigned, unsigned, unsigned, unsigned, unsigned, unsigned long long n,
+    const unsigned char [n], unsigned m, char [m],
+    long long [static NISSY_SIZE_SOLVE_STATS], int (*)(void *), void *);
 STATIC_INLINE bool solve_h48_stop(dfsarg_solve_h48_t [static 1]);
 STATIC int64_t solve_h48_maketasks(
     dfsarg_solve_h48_t [static 1], dfsarg_solve_h48_maketasks_t [static 1],
@@ -61,6 +65,36 @@ STATIC int64_t solve_h48(oriented_cube_t, uint8_t, uint8_t, uint8_t, uint8_t,
     uint8_t, uint64_t, const unsigned char *, size_t n, char [n],
     long long [static NISSY_SIZE_SOLVE_STATS], int (*)(void *), void *);
 
+STATIC long long solve_h48_dispatch(
+        oriented_cube_t oc,
+        const char *solver,
+        unsigned nissflag,
+        unsigned minmoves,
+        unsigned maxmoves,
+        unsigned maxsols,
+        unsigned optimal,
+        unsigned threads,
+        unsigned long long data_size,
+        const unsigned char data[data_size],
+        unsigned sols_size,
+        char sols[sols_size],
+        long long stats[static NISSY_SIZE_SOLVE_STATS],
+        int (*poll_status)(void *),
+        void *poll_status_data
+)
+{
+        uint8_t h, k;
+        long long err;
+
+        err = parse_h48_hk(solver, &h, &k);
+        if (err != NISSY_OK)
+                return err;
+
+        return solve_h48(oc, minmoves, maxmoves, maxsols, optimal, threads,
+            data_size, data, sols_size, sols, stats,
+            poll_status, poll_status_data);
+}
+
 STATIC_INLINE bool
 solve_h48_stop(dfsarg_solve_h48_t arg[static 1])
 {
diff --git a/src/solvers/h48/utils.h b/src/solvers/h48/utils.h
new file mode 100644
index 0000000..b266c66
--- /dev/null
+++ b/src/solvers/h48/utils.h
@@ -0,0 +1,66 @@
+long long parse_h48_hk(
+    const char *, uint8_t [static 1], uint8_t [static 1]);
+STATIC long long dataid_h48(const char *, char [static NISSY_SIZE_DATAID]);
+
+long long
+parse_h48_hk(const char *buf, uint8_t h[static 1], uint8_t k[static 1])
+{
+        char format_error_msg[100];
+        sprintf(format_error_msg, "[H48] Error parsing H48 solver: must be in "
+            "'h48h*k*' format, but got '%s'\n", buf);
+
+        buf += 3;
+
+        if (*buf != 'h') {
+                LOG(format_error_msg);
+                goto parse_h48_hk_error;
+        }
+        buf++;
+
+        *h = atoi(buf);
+        if (*h > 11) {
+                LOG("[H48] Invalid value %" PRIu8 " for parameter h\n", *h);
+                goto parse_h48_hk_error;
+        }
+
+        for ( ; *buf >= 0 + '0' && *buf <= 9 + '0'; buf++) {
+                if (*buf == 0) {
+                        LOG(format_error_msg);
+                        goto parse_h48_hk_error;
+                }
+        }
+
+        if (*buf != 'k') {
+                LOG(format_error_msg);
+                goto parse_h48_hk_error;
+        }
+        buf++;
+
+        *k = atoi(buf);
+        if (!(*k == 2 || (*k == 4 && *h == 0))) {
+                LOG("[H48] Invalid combinations of values h=%" PRIu8 " and k=%"
+                    PRIu8 " for parameters h and k\n", *h, *k);
+                goto parse_h48_hk_error;
+        }
+
+        return NISSY_OK;
+
+parse_h48_hk_error:
+        *h = 0;
+        *k = 0;
+        return NISSY_ERROR_INVALID_SOLVER;
+}
+
+STATIC long long
+dataid_h48(const char *hk, char buf[static NISSY_SIZE_DATAID])
+{
+        uint8_t h, k;
+        long long err;
+
+        err = parse_h48_hk(hk, &h, &k);
+        if (err < 0)
+                return err;
+
+        sprintf(buf, "h48h%" PRIu8 "k%" PRIu8, h, k);
+        return NISSY_OK;
+}
diff --git a/src/solvers/solvers.h b/src/solvers/solvers.h
index 4d6bbca..27ae627 100644
--- a/src/solvers/solvers.h
+++ b/src/solvers/solvers.h
@@ -2,5 +2,7 @@
 #include "solutions.h"
 #include "tables_types_macros.h"
 #include "tables.h"
+#include "distribution.h"
 #include "h48/h48.h"
 #include "coord/coord.h"
+#include "dispatch.h"