Big cleanup for appendsolution()

With this PR the appendsolution routine is extracted from the h48
solver and the new coordinate solver and made generic. This has
many advantages:
- less repetition (even if the two versions are different enough that
  *for now* it was not a big deal)
- smaller h48/solve.h file, which is already a big beast
- easier to test the appendsolution() routine separately

1 files changed, 38 insertions, 3 deletions

diff --git a/src/core/io_moves.h b/src/core/io_moves.h
index fa91e8b..8c56a9f 100644
--- a/src/core/io_moves.h
+++ b/src/core/io_moves.h
@@ -1,6 +1,26 @@
 STATIC uint8_t readmove(char);
+STATIC int64_t readmoves(const char *, size_t n, uint8_t [n]);
 STATIC uint8_t readmodifier(char);
-STATIC int64_t writemoves(size_t n, uint8_t [n], size_t m, char [m]);
+STATIC int64_t writemoves(size_t n, const uint8_t [n], size_t m, char [m]);
+
+#define FOREACH_READMOVE(ARG_BUF, ARG_MOVE, ARG_C, ARG_MAX, \
+        RET_ERROR, ARG_ACTION) \
+        const char *VAR_B; \
+        uint8_t VAR_MOVE_NOMOD, VAR_MOD; \
+        for (VAR_B = ARG_BUF, ARG_C = 0; *VAR_B != '\0'; VAR_B++, ARG_C++) { \
+                while (*VAR_B == ' ' || *VAR_B == '\t' || *VAR_B == '\n') \
+                        VAR_B++; \
+                if (*VAR_B == '\0' || ARG_C == ARG_MAX) \
+                        break; \
+                if ((VAR_MOVE_NOMOD = readmove(*VAR_B)) == UINT8_ERROR) { \
+                        LOG("Error: unknown move '%c'\n", *VAR_B); \
+                        return RET_ERROR; \
+                } \
+                if ((VAR_MOD = readmodifier(*(VAR_B+1))) != 0) \
+                        VAR_B++; \
+                ARG_MOVE = VAR_MOVE_NOMOD + VAR_MOD; \
+                ARG_ACTION \
+        }
 
 STATIC uint8_t
 readmove(char c)
@@ -39,9 +59,22 @@ readmodifier(char c)
 }
 
 STATIC int64_t
+readmoves(const char *buf, size_t n, uint8_t ret[n])
+{
+        uint8_t m;
+        uint64_t c;
+
+        FOREACH_READMOVE(buf, m, c, n, NISSY_ERROR_INVALID_MOVES,
+                ret[c] = m;
+        )
+
+        return (int64_t)c;
+}
+
+STATIC int64_t
 writemoves(
         size_t nmoves,
-        uint8_t m[nmoves],
+        const uint8_t m[nmoves],
         size_t buf_size,
         char buf[buf_size]
 )
@@ -69,7 +102,9 @@ writemoves(
                 *b = ' ';
         }
 
-        if (b != buf)
+        if (b == buf)
+                written = 1; /* Nothing written, only NULL-terminator */
+        else
                 b--; /* Remove last space */
         *b = '\0';