Add project skeletonHEADmaster

1 files changed, 289 insertions, 0 deletions

diff --git a/pr.c b/pr.c
new file mode 100644
index 0000000..df2d127
--- /dev/null
+++ b/pr.c
@@ -0,0 +1,289 @@
+#include "pr.h"
+#include "errloc.h"
+#include "fn.h"
+#include "prv.h"
+#include "parse.h"
+#include "stmt.h"
+#include "storage.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static int pryy(const struct lex *l, struct prv *p);
+static int pryn(const struct lex *l, struct prv *p);
+static int prny(const struct lex *l, struct prv *p);
+static int prnn(const struct lex *l, struct prv *p);
+
+static const struct seq seqs[] =
+{
+    /* function definition with parameters and return variable */
+    {
+        (const struct step[])
+        {
+            {ID, "with"},
+            {ID, NULL, 1},
+            {ID, "returning"},
+            {ID},
+            {0}
+        },
+        .fn = pryy
+    },
+
+    /* function definition with parameters, no return variable */
+    {
+        (const struct step[])
+        {
+            {ID, "with"},
+            {ID, NULL, 1},
+            {0}
+        },
+
+        .fn = pryn
+    },
+
+    /* function definition with no parameters, with return variable */
+    {
+        (const struct step[])
+        {
+            {ID, "returning"},
+            {ID},
+            {0}
+        },
+
+        .fn = prny
+    },
+
+    {0}
+};
+
+static const struct tk *findparam(const char *s, const struct pr *pr)
+{
+    for (size_t i = 0; i < pr->nparams; i++)
+    {
+        const struct param *p = &pr->params[i];
+        const struct tk *tk = p->tk;
+
+        if (!strcmp(tk->s, s))
+            return tk;
+    }
+
+    return NULL;
+}
+
+static int param(const struct tk *tk, const struct stentry *e, struct pr *pr)
+{
+    size_t n = pr->nparams + 1;
+    struct param *params = realloc(pr->params, n * sizeof *params);
+
+    if (!params)
+    {
+        perror("realloc(3)");
+        return -1;
+    }
+
+    pr->params = params;
+    pr->params[pr->nparams++] = (struct param){.tk = tk, .entry = e};
+    return 0;
+}
+
+static int setret(const struct tk *tk, const struct stentry *e, struct pr *pr)
+{
+    if (!(pr->ret = malloc(sizeof *pr->ret)))
+    {
+        perror("malloc(3)");
+        return -1;
+    }
+
+    *pr->ret = (struct param){.tk = tk, .entry = e};
+    return 0;
+}
+
+static int finalize(struct prv *p)
+{
+    const struct fn *fn = fn_cur(p);
+    const struct pr *pr = fn->pr;
+    struct pos init =
+    {
+        .seq = stmts,
+        .stseq = stmts,
+        .step = stmts->steps
+    };
+
+    if (push(&init, p))
+        return -1;
+
+    fprintf(stderr, "\tadding pr with %zu parameters and%s return value\n",
+        pr->nparams, pr->ret ? "" : " no");
+    p->stk = p->tk;
+    return 1;
+}
+
+static int prret(const struct lex *l, const struct tk *tk, struct prv *p)
+{
+    const struct fn *fn = fn_cur(p);
+    struct pr *pr = fn->pr;
+    const char *s = tk->s;
+    const struct storage *lk = fn->lk, *gl = fn->gl;
+    const struct stentry *e, *gle;
+    const struct tk *prm;
+
+    if (!lk || !(e = storage_find(s, lk)))
+    {
+        errloc(tk, "return value \"%s\" not in %s", s, lk->name);
+        return -1;
+    }
+    else if (gl && (gle = storage_find(s, gl)))
+    {
+        const struct loc *loc = &gle->tk->loc;
+
+        errloc(tk, "return value \"%s\" also in %s at %d:%d", s, gl->name,
+            loc->line, loc->col);
+        return -1;
+    }
+    else if ((prm = findparam(s, pr)))
+    {
+        const struct loc *loc = &prm->loc;
+
+        errloc(tk, "return value \"%s\" already listed as "
+            "parameter at %s:%d:%d", tk->s, loc->f, loc->line, loc->col);
+        return -1;
+    }
+    else if (setret(tk, e, pr))
+        return -1;
+
+    return finalize(p);
+}
+
+static const struct tk *prparams(const struct lex *l, struct prv *p, int *ret)
+{
+    const struct tk *tk = p->stk + 1;
+    const struct fn *fn = fn_cur(p);
+    struct pr *pr = fn->pr;
+
+    if (ret)
+        *ret = 0;
+
+    for (;;)
+    {
+        const char *s = tk->s;
+        const struct stentry *e, *gle;
+        const struct tk *prm;
+        const struct storage *lk = fn->lk, *gl = fn->gl;
+
+        if (kw(s) && strcmp(s, "returning"))
+            return tk;
+        else if (!strcmp(s, "returning") && ret)
+        {
+            *ret = 1;
+            return ++tk;
+        }
+        else if ((prm = findparam(s, pr)))
+        {
+            const struct loc *loc = &prm->loc;
+
+            errloc(tk, "parameter \"%s\" already listed at %d:%d", s,
+                loc->line, loc->col);
+            return NULL;
+        }
+        else if (!lk || !(e = storage_find(s, lk)))
+        {
+            errloc(tk, "parameter \"%s\" not in %s", s, lk->name);
+            return NULL;
+        }
+        else if (gl && (gle = storage_find(s, gl)))
+        {
+            const struct loc *loc = &gle->tk->loc;
+
+            errloc(tk, "parameter \"%s\" also in %s at %d:%d", s, gl->name,
+                loc->line, loc->col);
+            return NULL;
+        }
+        else if (param(tk, e, pr))
+            return NULL;
+        else
+            tk++;
+    }
+
+    return tk;
+}
+
+static int pryy(const struct lex *l, struct prv *p)
+{
+    int ret;
+    const struct tk *tk = prparams(l, p, &ret);
+
+    if (!tk)
+        return -1;
+    else if (ret)
+        return prret(l, tk, p);
+
+    return finalize(p);
+}
+
+static int pryn(const struct lex *l, struct prv *p)
+{
+    if (!prparams(l, p, NULL))
+        return -1;
+
+    return finalize(p);
+}
+
+static int prny(const struct lex *l, struct prv *p)
+{
+    return prret(l, p->stk + 1, p);
+}
+
+static int prnn(const struct lex *l, struct prv *p)
+{
+    return finalize(p);
+}
+
+void pr_free(struct pr *pr)
+{
+    if (pr)
+    {
+        free(pr->params);
+        free(pr->ret);
+    }
+
+    free(pr);
+}
+
+int pr(const struct lex *l, struct prv *p)
+{
+    const struct tk *tk = p->tk - 1, *next = p->tk;
+    struct fn *fn = fn_cur(p);
+    struct pos init =
+    {
+        .seq = seqs,
+        .stseq = seqs,
+        .step = seqs->steps
+    };
+
+    if (fn->pr)
+    {
+        const struct loc *loc = &fn->pr->tk->loc;
+
+        errloc(tk, "pr already defined at %s:%d:%d", loc->f, loc->line,
+            loc->col);
+        return -1;
+    }
+    else if (!((fn->pr = malloc(sizeof *fn->pr))))
+    {
+        perror("malloc(3)");
+        return -1;
+    }
+
+    *fn->pr = (struct pr){.tk = tk};
+
+    /* on no parameters or return values, go directly to next sequences list. */
+    if (next - l->tokens < l->ntok
+        && strcmp(next->s, "with")
+        && strcmp(next->s, "returning"))
+        return prnn(l, p);
+    else if (push(&init, p))
+        return -1;
+
+    p->stk = p->tk;
+    return 1;
+}