ref: 84cd9f2db9bea744d99b2afc2c89d480732c3e23
dir: /src/asm/symbol.c/
/*
* This file is part of RGBDS.
*
* Copyright (c) 1997-2018, Carsten Sorensen and RGBDS contributors.
*
* SPDX-License-Identifier: MIT
*/
/*
* Symboltable and macroargs stuff
*/
#include <assert.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include "asm/asm.h"
#include "asm/fstack.h"
#include "asm/macro.h"
#include "asm/main.h"
#include "asm/mymath.h"
#include "asm/section.h"
#include "asm/symbol.h"
#include "asm/util.h"
#include "asm/warning.h"
#include "extern/err.h"
#include "hashmap.h"
#include "helpers.h"
#include "version.h"
HashMap symbols;
static struct sSymbol *pScope; /* Current section symbol scope */
struct sSymbol *pPCSymbol;
static struct sSymbol *p_NARGSymbol;
static struct sSymbol *p__LINE__Symbol;
static char SavedTIME[256];
static char SavedDATE[256];
static char SavedTIMESTAMP_ISO8601_LOCAL[256];
static char SavedTIMESTAMP_ISO8601_UTC[256];
static char SavedDAY[3];
static char SavedMONTH[3];
static char SavedYEAR[20];
static char SavedHOUR[3];
static char SavedMINUTE[3];
static char SavedSECOND[3];
static bool exportall;
struct ForEachArgs {
void (*func)(struct sSymbol *, void *);
void *arg;
};
static void forEachWrapper(void *_symbol, void *_argWrapper)
{
struct ForEachArgs *argWrapper = _argWrapper;
struct sSymbol *symbol = _symbol;
argWrapper->func(symbol, argWrapper->arg);
}
void sym_ForEach(void (*func)(struct sSymbol *, void *), void *arg)
{
struct ForEachArgs argWrapper = { .func = func, .arg = arg };
hash_ForEach(symbols, forEachWrapper, &argWrapper);
}
static int32_t Callback_NARG(struct sSymbol const *self)
{
(void)self;
return macro_NbArgs();
}
static int32_t Callback__LINE__(struct sSymbol const *self)
{
(void)self;
return nLineNo;
}
static int32_t CallbackPC(struct sSymbol const *self)
{
return self->pSection ? self->pSection->nOrg + curOffset : 0;
}
/*
* Get the nValue field of a symbol
*/
int32_t sym_GetValue(struct sSymbol const *sym)
{
if (sym->Callback)
return sym->Callback(sym);
if (sym->type == SYM_LABEL)
return sym->nValue + sym->pSection->nOrg;
return sym->nValue;
}
/*
* Update a symbol's definition filename and line
*/
static void updateSymbolFilename(struct sSymbol *nsym)
{
if (snprintf(nsym->tzFileName, _MAX_PATH + 1, "%s",
tzCurrentFileName) > _MAX_PATH) {
fatalerror("%s: File name is too long: '%s'", __func__,
tzCurrentFileName);
}
nsym->nFileLine = fstk_GetLine();
}
/*
* Create a new symbol by name
*/
static struct sSymbol *createsymbol(char const *s)
{
struct sSymbol *symbol = malloc(sizeof(*symbol));
if (!symbol)
fatalerror("Failed to create symbol: %s", strerror(errno));
if (snprintf(symbol->tzName, MAXSYMLEN + 1, "%s", s) > MAXSYMLEN)
warning(WARNING_LONG_STR, "Symbol name is too long: '%s'", s);
hash_AddElement(symbols, symbol->tzName, symbol);
symbol->isExported = false;
symbol->isBuiltin = false;
symbol->pScope = NULL;
symbol->pSection = NULL;
symbol->nValue = 0; /* TODO: is this necessary? */
symbol->pMacro = NULL;
symbol->Callback = NULL;
symbol->ID = -1;
symbol->next = NULL;
updateSymbolFilename(symbol);
return symbol;
}
/*
* Creates the full name of a local symbol in a given scope, by prepending
* the name with the parent symbol's name.
*/
static void fullSymbolName(char *output, size_t outputSize,
char const *localName, const struct sSymbol *scope)
{
const struct sSymbol *parent = scope->pScope ? scope->pScope : scope;
int n = snprintf(output, outputSize, "%s%s", parent->tzName, localName);
if (n >= (int)outputSize)
fatalerror("Symbol name is too long: '%s%s'",
parent->tzName, localName);
}
/*
* Find a symbol by name and scope
*/
static struct sSymbol *findsymbol(char const *s, struct sSymbol const *scope)
{
char fullname[MAXSYMLEN + 1];
if (s[0] == '.' && scope) {
fullSymbolName(fullname, sizeof(fullname), s, scope);
s = fullname;
}
char const *separator = strchr(s, '.');
if (separator && strchr(separator + 1, '.'))
fatalerror("'%s' is a nonsensical reference to a nested local symbol",
s);
return hash_GetElement(symbols, s);
}
/*
* Find a symbol by name, with automatically determined scope
*/
struct sSymbol *sym_FindSymbol(char const *tzName)
{
struct sSymbol *pscope;
if (*tzName == '.')
pscope = pScope;
else
pscope = NULL;
return findsymbol(tzName, pscope);
}
static inline bool isReferenced(struct sSymbol const *sym)
{
return sym->ID != -1;
}
/*
* Purge a symbol
*/
void sym_Purge(char const *tzName)
{
struct sSymbol *scope = tzName[0] == '.' ? pScope : NULL;
struct sSymbol *symbol = findsymbol(tzName, scope);
if (!symbol) {
yyerror("'%s' not defined", tzName);
} else if (symbol->isBuiltin) {
yyerror("Built-in symbol '%s' cannot be purged", tzName);
} else if (isReferenced(symbol)) {
yyerror("Symbol \"%s\" is referenced and thus cannot be purged",
tzName);
} else {
hash_RemoveElement(symbols, tzName);
free(symbol->pMacro);
free(symbol);
}
}
/*
* Return a constant symbols value
*/
uint32_t sym_GetConstantValue(char const *s)
{
struct sSymbol const *psym = sym_FindSymbol(s);
if (psym == pPCSymbol) {
if (!pCurrentSection)
yyerror("PC has no value outside a section");
else if (pCurrentSection->nOrg == -1)
yyerror("Expected constant PC but section is not fixed");
else
return sym_GetValue(psym);
} else if (psym != NULL) {
if (sym_IsConstant(psym))
return sym_GetValue(psym);
yyerror("\"%s\" does not have a constant value", s);
} else {
yyerror("'%s' not defined", s);
}
return 0;
}
/*
* Return a defined symbols value... aborts if not defined yet
*/
uint32_t sym_GetDefinedValue(char const *s)
{
struct sSymbol const *psym = sym_FindSymbol(s);
if (psym != NULL) {
if (sym_IsDefined(psym)) {
if (!sym_IsNumeric(psym))
yyerror("'%s' is a macro or string symbol", s);
return sym_GetValue(psym);
}
}
yyerror("'%s' not defined", s);
return 0;
}
struct sSymbol *sym_GetCurrentSymbolScope(void)
{
return pScope;
}
void sym_SetCurrentSymbolScope(struct sSymbol *pNewScope)
{
pScope = pNewScope;
}
/*
* Find a macro by name
*/
struct sSymbol *sym_FindMacro(char const *s)
{
return findsymbol(s, NULL);
}
/*
* Create a symbol that will be non-relocatable and ensure that it
* hasn't already been defined or referenced in a context that would
* require that it be relocatable
*/
static struct sSymbol *createNonrelocSymbol(char const *tzSym)
{
struct sSymbol *nsym = findsymbol(tzSym, NULL);
if (nsym != NULL) {
if (sym_IsDefined(nsym)) {
yyerror("'%s' already defined at %s(%u)",
tzSym, nsym->tzFileName, nsym->nFileLine);
} else {
yyerror("'%s' referenced as label at %s(%u)",
tzSym, nsym->tzFileName, nsym->nFileLine);
}
} else {
nsym = createsymbol(tzSym);
}
return nsym;
}
/*
* Add an equated symbol
*/
struct sSymbol *sym_AddEqu(char const *tzSym, int32_t value)
{
struct sSymbol *nsym = createNonrelocSymbol(tzSym);
nsym->nValue = value;
nsym->type = SYM_EQU;
nsym->pScope = NULL;
updateSymbolFilename(nsym);
return nsym;
}
/*
* Add a string equated symbol.
*
* If the desired symbol is a string it needs to be passed to this function with
* quotes inside the string, like sym_AddString("name", "\"test\"), or the
* assembler won't be able to use it with DB and similar. This is equivalent to
* ``` name EQUS "\"test\"" ```
*
* If the desired symbol is a register or a number, just the terminator quotes
* of the string are enough: sym_AddString("M_PI", "3.1415"). This is the same
* as ``` M_PI EQUS "3.1415" ```
*/
struct sSymbol *sym_AddString(char const *tzSym, char const *tzValue)
{
struct sSymbol *nsym = createNonrelocSymbol(tzSym);
nsym->pMacro = malloc(strlen(tzValue) + 1);
if (nsym->pMacro != NULL)
strcpy(nsym->pMacro, tzValue);
else
fatalerror("No memory for string equate");
nsym->type = SYM_EQUS;
nsym->ulMacroSize = strlen(tzValue);
nsym->pScope = NULL;
return nsym;
}
/*
* Alter a SET symbols value
*/
struct sSymbol *sym_AddSet(char const *tzSym, int32_t value)
{
struct sSymbol *nsym = findsymbol(tzSym, NULL);
if (nsym != NULL) {
if (sym_IsDefined(nsym)) {
if (nsym->type == SYM_LABEL)
yyerror("'%s' already defined as non-constant at %s(%u)",
tzSym,
nsym->tzFileName,
nsym->nFileLine);
else if (nsym->type != SYM_SET)
yyerror("'%s' already defined as constant at %s(%u)",
tzSym,
nsym->tzFileName,
nsym->nFileLine);
} else if (nsym->type == SYM_REF) {
yyerror("'%s' already referenced at %s(%u)",
tzSym,
nsym->tzFileName,
nsym->nFileLine);
}
} else {
nsym = createsymbol(tzSym);
}
nsym->nValue = value;
nsym->type = SYM_SET;
nsym->pScope = NULL;
updateSymbolFilename(nsym);
return nsym;
}
/*
* Add a local (.name) relocatable symbol
*/
struct sSymbol *sym_AddLocalReloc(char const *tzSym)
{
if (pScope) {
char fullname[MAXSYMLEN + 1];
fullSymbolName(fullname, sizeof(fullname), tzSym, pScope);
return sym_AddReloc(fullname);
} else {
yyerror("Local label '%s' in main scope", tzSym);
return NULL;
}
}
/*
* Add a relocatable symbol
*/
struct sSymbol *sym_AddReloc(char const *tzSym)
{
struct sSymbol *scope = NULL;
struct sSymbol *nsym;
char *localPtr = strchr(tzSym, '.');
if (localPtr != NULL) {
if (!pScope) {
yyerror("Local label in main scope");
return NULL;
}
struct sSymbol *parent = pScope->pScope ?
pScope->pScope : pScope;
uint32_t parentLen = localPtr - tzSym;
if (strchr(localPtr + 1, '.') != NULL)
fatalerror("'%s' is a nonsensical reference to a nested local symbol",
tzSym);
else if (strlen(parent->tzName) != parentLen
|| strncmp(tzSym, parent->tzName, parentLen) != 0)
yyerror("Not currently in the scope of '%.*s'",
parentLen, tzSym);
scope = parent;
}
nsym = findsymbol(tzSym, scope);
if (!nsym)
nsym = createsymbol(tzSym);
else if (sym_IsDefined(nsym))
yyerror("'%s' already defined in %s(%d)", tzSym,
nsym->tzFileName, nsym->nFileLine);
/* If the symbol already exists as a ref, just "take over" it */
nsym->nValue = curOffset;
nsym->type = SYM_LABEL;
if (exportall)
nsym->isExported = true;
nsym->pScope = scope;
nsym->pSection = sect_GetSymbolSection();
/* Labels need to be assigned a section, except PC */
if (!pCurrentSection && strcmp(tzSym, "@"))
yyerror("Label \"%s\" created outside of a SECTION",
tzSym);
updateSymbolFilename(nsym);
pScope = findsymbol(tzSym, scope);
return pScope;
}
/*
* Export a symbol
*/
void sym_Export(char const *tzSym)
{
struct sSymbol *nsym = sym_FindSymbol(tzSym);
/* If the symbol doesn't exist, create a ref that can be purged */
if (!nsym)
nsym = sym_Ref(tzSym);
nsym->isExported = true;
}
/*
* Add a macro definition
*/
struct sSymbol *sym_AddMacro(char const *tzSym, int32_t nDefLineNo)
{
struct sSymbol *nsym = createNonrelocSymbol(tzSym);
nsym->type = SYM_MACRO;
nsym->pScope = NULL;
nsym->ulMacroSize = ulNewMacroSize;
nsym->pMacro = tzNewMacro;
updateSymbolFilename(nsym);
/*
* The symbol is created at the line after the `endm`,
* override this with the actual definition line
*/
nsym->nFileLine = nDefLineNo;
return nsym;
}
/*
* Flag that a symbol is referenced in an RPN expression
* and create it if it doesn't exist yet
*/
struct sSymbol *sym_Ref(char const *tzSym)
{
struct sSymbol *nsym = sym_FindSymbol(tzSym);
if (nsym == NULL) {
char fullname[MAXSYMLEN + 1];
if (*tzSym == '.') {
if (!pScope)
fatalerror("Local label reference '%s' in main scope",
tzSym);
fullSymbolName(fullname, sizeof(fullname), tzSym,
pScope);
tzSym = fullname;
}
nsym = createsymbol(tzSym);
nsym->type = SYM_REF;
}
return nsym;
}
/*
* Set whether to export all relocatable symbols by default
*/
void sym_SetExportAll(bool set)
{
exportall = set;
}
/**
* Returns a pointer to the first non-zero character in a string
* Non-'0', not non-'\0'.
*/
static inline char const *removeLeadingZeros(char const *ptr)
{
while (*ptr == '0')
ptr++;
return ptr;
}
/*
* Initialize the symboltable
*/
void sym_Init(void)
{
pPCSymbol = sym_AddReloc("@");
pPCSymbol->Callback = CallbackPC;
pPCSymbol->isBuiltin = true;
p_NARGSymbol = sym_AddEqu("_NARG", 0);
p_NARGSymbol->Callback = Callback_NARG;
p_NARGSymbol->isBuiltin = true;
p__LINE__Symbol = sym_AddEqu("__LINE__", 0);
p__LINE__Symbol->Callback = Callback__LINE__;
p__LINE__Symbol->isBuiltin = true;
struct sSymbol *_RSSymbol = sym_AddSet("_RS", 0);
_RSSymbol->isBuiltin = true;
time_t now = time(NULL);
if (now == (time_t)-1) {
warn("Couldn't determine current time");
/* Fall back by pretending we are at the Epoch */
now = 0;
}
const struct tm *time_utc = gmtime(&now);
const struct tm *time_local = localtime(&now);
strftime(SavedTIME, sizeof(SavedTIME), "\"%H:%M:%S\"",
time_local);
strftime(SavedDATE, sizeof(SavedDATE), "\"%d %B %Y\"",
time_local);
strftime(SavedTIMESTAMP_ISO8601_LOCAL,
sizeof(SavedTIMESTAMP_ISO8601_LOCAL), "\"%Y-%m-%dT%H-%M-%S%z\"",
time_local);
strftime(SavedTIMESTAMP_ISO8601_UTC,
sizeof(SavedTIMESTAMP_ISO8601_UTC), "\"%Y-%m-%dT%H-%M-%SZ\"",
time_utc);
strftime(SavedYEAR, sizeof(SavedYEAR), "%Y", time_utc);
strftime(SavedMONTH, sizeof(SavedMONTH), "%m", time_utc);
strftime(SavedDAY, sizeof(SavedDAY), "%d", time_utc);
strftime(SavedHOUR, sizeof(SavedHOUR), "%H", time_utc);
strftime(SavedMINUTE, sizeof(SavedMINUTE), "%M", time_utc);
strftime(SavedSECOND, sizeof(SavedSECOND), "%S", time_utc);
#define addString(name, val) do { \
struct sSymbol *symbol = sym_AddString(name, val); \
symbol->isBuiltin = true; \
} while (0)
addString("__TIME__", SavedTIME);
addString("__DATE__", SavedDATE);
addString("__ISO_8601_LOCAL__", SavedTIMESTAMP_ISO8601_LOCAL);
addString("__ISO_8601_UTC__", SavedTIMESTAMP_ISO8601_UTC);
/* This cannot start with zeros */
addString("__UTC_YEAR__", SavedYEAR);
addString("__UTC_MONTH__", removeLeadingZeros(SavedMONTH));
addString("__UTC_DAY__", removeLeadingZeros(SavedDAY));
addString("__UTC_HOUR__", removeLeadingZeros(SavedHOUR));
addString("__UTC_MINUTE__", removeLeadingZeros(SavedMINUTE));
addString("__UTC_SECOND__", removeLeadingZeros(SavedSECOND));
#undef addString
pScope = NULL;
math_DefinePI();
}