telodendria/tools/tp.c
Jordan Bancino 70dbdf0a1e Add tp, a simple but powerful text preprocessor.
I might rename it, and I have yet to document it in a man page, but I have
found this extremely useful so I thought I'd give it a home here.
2023-07-29 00:04:42 +00:00

754 lines
15 KiB
C

/*
* Copyright (C) 2022-2023 Jordan Bancino <@jordan:bancino.net>
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation files
* (the "Software"), to deal in the Software without restriction,
* including without limitation the rights to use, copy, modify, merge,
* publish, distribute, sublicense, and/or sell copies of the Software,
* and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <Args.h>
#include <Memory.h>
#include <Array.h>
#include <HashMap.h>
#include <Str.h>
#include <Stream.h>
#define BLOCK 64
/*
* Anything that can be done in the language itself should; to
* keep the interpreter minimal. Note that this has the side effect
* of allowing the runtime to become corrupted or undefined which
* may lead to confusing behavior, but the language primitives
* cannot be corrupted, so things can always be corrected.
*/
static char runtime[] =
"[def let; name, value; [eval [(]def [name][;][;][value][)]]]"
"[def not; cond; [if [cond];;true]]"
"[def (); str; [(][str][)]]"
"[def #;;]"
"[def //;;]"
;
static Stream *err;
static int debug;
typedef struct Definition
{
Array *args;
char *body;
} Definition;
static char *
EvalExpr(char *expr, Array * stack);
static char *
ReadExpr(Stream * in)
{
size_t len = 0;
size_t size = 0;
size_t level = 1;
int c;
char *expr;
char *tmp;
size += BLOCK;
expr = Malloc(size * sizeof(char));
if (!expr)
{
return NULL;
}
while ((c = StreamGetc(in)) != EOF)
{
if (len + 1 >= size)
{
size += BLOCK;
tmp = Realloc(expr, size * sizeof(char));
if (!tmp)
{
Free(expr);
return NULL;
}
expr = tmp;
}
if (c == ']')
{
if (level > 0)
{
level--;
}
if (!level)
{
break;
}
}
if (c == '[')
{
level++;
}
expr[len] = c;
len++;
}
expr[len] = '\0';
return expr;
}
static char *
Eval(char **argp, Array * stack)
{
size_t len;
size_t size;
char *res;
char *tmp;
char *arg = *argp;
len = 0;
size = BLOCK;
res = Malloc(size * sizeof(char));
if (!res)
{
return NULL;
}
while (*arg)
{
if (len + 1 >= size)
{
size += BLOCK;
tmp = Realloc(res, size * sizeof(char));
if (!tmp)
{
Free(res);
return NULL;
}
res = tmp;
}
if (*arg == ';')
{
res[len] = '\0';
break;
}
else if (*arg == '[')
{
size_t level = 1;
char *endp;
char *evalRes;
char *base;
arg++;
endp = arg;
while (level && *endp)
{
if (*endp == ']')
{
if (level > 0)
{
level--;
}
if (!level)
{
break;
}
}
else if (*endp == '[')
{
level++;
}
endp++;
}
*endp = '\0';
evalRes = EvalExpr(arg, stack);
base = evalRes;
while (*evalRes)
{
if (len + 1 >= size)
{
size += BLOCK;
tmp = Realloc(res, size * sizeof(char));
if (!tmp)
{
Free(base);
Free(res);
return NULL;
}
res = tmp;
}
res[len] = *evalRes;
len++;
evalRes++;
}
Free(base);
*endp = ']';
arg = endp;
}
else
{
res[len] = *arg;
len++;
}
arg++;
}
if (*arg == ';')
{
arg++;
while (isspace(*arg))
{
arg++;
}
}
res[len] = '\0';
*argp = arg;
return res;
}
static char *
EvalExpr(char *expr, Array * stack)
{
char *argv = expr;
char *op = expr;
char ops;
char *opi;
char *res;
while (*argv && !isspace(*argv))
{
argv++;
}
ops = *argv;
opi = argv;
*argv = '\0';
argv++;
if (StrEquals(op, "("))
{
res = StrDuplicate("[");
}
else if (StrEquals(op, ")"))
{
res = StrDuplicate("]");
}
else if (StrEquals(op, ";"))
{
res = StrDuplicate(";");
}
else if (StrEquals(op, "env"))
{
char *env = Eval(&argv, stack);
char *val = getenv(env);
Free(env);
if (!val)
{
val = "";
}
res = StrDuplicate(val);
}
else if (StrEquals(op, "eval"))
{
char *expr = Eval(&argv, stack);
char *tmp = expr;
res = Eval(&tmp, stack);
Free(expr);
}
else if (StrEquals(op, "if"))
{
char *cond = Eval(&argv, stack);
/*
* If the condition is false, seek past the true argument
* without evaluating it.
*/
if (StrBlank(cond))
{
size_t level = 0;
while (*argv)
{
switch (*argv)
{
case '[':
level++;
break;
case ']':
if (level > 0)
{
level--;
}
break;
case ';':
if (!level)
{
argv++;
while (isspace(*argv))
{
argv++;
}
goto end_loop;
}
break;
}
argv++;
}
}
end_loop:
res = Eval(&argv, stack);
Free(cond);
}
else if (StrEquals(op, "eq?"))
{
char *s1 = Eval(&argv, stack);
char *s2 = Eval(&argv, stack);
if (StrEquals(s1, s2))
{
res = StrDuplicate("true");
}
else
{
res = StrDuplicate("");
}
Free(s1);
Free(s2);
}
else if (StrEquals(op, "def?"))
{
Definition *def;
size_t i;
char *directive = Eval(&argv, stack);
for (i = 0; i < ArraySize(stack); i++)
{
HashMap *stackFrame = ArrayGet(stack, i);
def = HashMapGet(stackFrame, directive);
if (def)
{
break;
}
}
if (def)
{
res = StrDuplicate("true");
}
else
{
res = StrDuplicate("");
}
Free(directive);
}
else if (StrEquals(op, "print"))
{
char *msg = Eval(&argv, stack);
StreamPrintf(err, msg);
Free(msg);
res = StrDuplicate("");
}
else if (StrEquals(op, "def"))
{
char *name = Eval(&argv, stack);
char *args = Eval(&argv, stack);
char *body = argv;
char *tok;
HashMap *stackFrame;
size_t i;
Definition *def = Malloc(sizeof(Definition));
def->body = StrDuplicate(body);
def->args = ArrayCreate();
if (debug)
{
StreamPrintf(err, "(def op = '%s', args = [", name);
}
tok = strtok(args, ",");
while (tok)
{
while (isspace(*tok))
{
tok++;
}
ArrayAdd(def->args, StrDuplicate(tok));
if (debug)
{
StreamPrintf(err, "'%s', ", tok);
}
tok = strtok(NULL, ",");
}
if (debug)
{
StreamPrintf(err, "], body = '%s')\n", def->body);
}
Free(args);
stackFrame = ArrayGet(stack, ArraySize(stack) - 1);
def = HashMapSet(stackFrame, name, def);
if (def)
{
for (i = 0; i < ArraySize(def->args); i++)
{
Free(ArrayGet(def->args, i));
}
ArrayFree(def->args);
Free(def->body);
Free(def);
}
Free(name);
res = StrDuplicate("");
}
else if (StrEquals(op, "undef"))
{
char *name = Eval(&argv, stack);
HashMap *stackFrame = ArrayGet(stack, ArraySize(stack) - 1);
Definition *def = HashMapDelete(stackFrame, name);
Free(name);
if (def)
{
size_t i;
for (i = 0; i < ArraySize(def->args); i++)
{
Free(ArrayGet(def->args, i));
}
ArrayFree(def->args);
Free(def->body);
Free(def);
}
res = StrDuplicate("");
}
else if (StrEquals(op, "include"))
{
char *fileName = Eval(&argv, stack);
Stream *file = StreamOpen(fileName, "r");
size_t size;
size_t len;
char c;
Free(fileName);
if (!file)
{
res = StrDuplicate("");
goto finish;
}
size = BLOCK;
len = 0;
res = Malloc(size * sizeof(char));
while ((c = StreamGetc(file)) != EOF)
{
if (len + 1 >= size)
{
size += BLOCK;
res = Realloc(res, size * sizeof(char));
}
res[len] = c;
len++;
}
res[len] = '\0';
StreamClose(file);
}
else
{
/* Locate macro on stack and execute it */
Definition *def;
char *body;
HashMap *stackFrame;
size_t i;
for (i = 0; i < ArraySize(stack); i++)
{
stackFrame = ArrayGet(stack, i);
def = HashMapGet(stackFrame, op);
if (def)
{
break;
}
}
if (!def)
{
res = StrDuplicate("");
goto finish;
}
stackFrame = HashMapCreate();
for (i = 0; i < ArraySize(def->args); i++)
{
char *argName = ArrayGet(def->args, i);
char *argVal = Eval(&argv, stack);
Definition *argDef = Malloc(sizeof(Definition));
argDef->args = NULL;
argDef->body = argVal;
HashMapSet(stackFrame, argName, argDef);
}
ArrayInsert(stack, 0, stackFrame);
body = def->body;
res = Eval(&body, stack);
ArrayDelete(stack, 0);
while (HashMapIterate(stackFrame, &body, (void **) &def))
{
for (i = 0; i < ArraySize(def->args); i++)
{
Free(ArrayGet(def->args, i));
}
ArrayFree(def->args);
Free(def->body);
Free(def);
}
HashMapFree(stackFrame);
}
finish:
*opi = ops;
return res;
}
static int
Process(Stream * in, Stream * out, Array * stack)
{
int c;
while ((c = StreamGetc(in)) != EOF)
{
if (c == '[')
{
char *expr;
char *res;
expr = ReadExpr(in);
res = EvalExpr(expr, stack);
StreamPuts(out, res);
StreamFlush(out);
Free(expr);
Free(res);
}
else
{
StreamPutc(out, c);
}
StreamFlush(out);
}
return 1;
}
int
Main(Array * args)
{
ArgParseState arg;
int opt;
int ret = EXIT_FAILURE;
size_t i;
Array *stack;
char *rt;
Stream *in;
Stream *out;
Array *eval = ArrayCreate();
debug = 0;
in = StreamStdin();
out = StreamStdout();
err = StreamStderr();
ArgParseStateInit(&arg);
while ((opt = ArgParse(&arg, args, "i:o:e:d")) != -1)
{
switch (opt)
{
case 'i':
if (StrEquals(arg.optArg, "-"))
{
in = StreamStdin();
}
in = StreamOpen(arg.optArg, "r");
if (!in)
{
StreamPrintf(err, "Unable to open '%s' for reading\n", arg.optArg);
goto finish;
}
break;
case 'o':
if (StrEquals(arg.optArg, "-"))
{
out = StreamStdout();
}
out = StreamOpen(arg.optArg, "w");
if (!out)
{
StreamPrintf(err, "Unable to open '%s' for writing.\n", arg.optArg);
goto finish;
}
break;
case 'e':
ArrayAdd(eval, StrDuplicate(arg.optArg));
break;
case 'd':
debug = 1;
break;
default:
goto finish;
}
}
stack = ArrayCreate();
ArrayAdd(stack, HashMapCreate());
/*
* Evaluate the runtime environment, discarding any
* output because the purpose is only to set the initial
* state, not to produce extra output.
*/
rt = runtime;
Free(Eval(&rt, stack));
/*
* Evaluate any expressions specified on the command line,
* interpolating them in the output if they produce anything
* because that is the expected behavior.
*/
for (i = 0; i < ArraySize(eval); i++)
{
char *expr = ArrayGet(eval, i);
char *res = Eval(&expr, stack);
StreamPuts(out, res);
Free(res);
}
Process(in, out, stack);
for (i = 0; i < ArraySize(stack); i++)
{
HashMap *stackFrame = ArrayGet(stack, i);
char *key;
Definition *val;
while (HashMapIterate(stackFrame, &key, (void **) &val))
{
size_t j;
for (j = 0; j < ArraySize(val->args); j++)
{
Free(ArrayGet(val->args, j));
}
ArrayFree(val->args);
Free(val->body);
Free(val);
}
HashMapFree(stackFrame);
}
ArrayFree(stack);
ret = EXIT_SUCCESS;
finish:
for (i = 0; i < ArraySize(eval); i++)
{
Free(ArrayGet(eval, i));
}
ArrayFree(eval);
if (in != StreamStdin())
{
StreamClose(in);
}
if (out != StreamStdout())
{
StreamClose(out);
}
return ret;
}