forked from lix-project/lix
559 lines
15 KiB
Plaintext
559 lines
15 KiB
Plaintext
%glr-parser
|
|
%pure-parser
|
|
%locations
|
|
%error-verbose
|
|
%defines
|
|
/* %no-lines */
|
|
%parse-param { yyscan_t scanner }
|
|
%parse-param { ParseData * data }
|
|
%lex-param { yyscan_t scanner }
|
|
|
|
|
|
%{
|
|
/* Newer versions of Bison copy the declarations below to
|
|
parser-tab.hh, which sucks bigtime since lexer.l doesn't want that
|
|
stuff. So allow it to be excluded. */
|
|
#ifndef BISON_HEADER_HACK
|
|
#define BISON_HEADER_HACK
|
|
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "aterm.hh"
|
|
#include "util.hh"
|
|
|
|
#include "parser-tab.hh"
|
|
#include "lexer-tab.hh"
|
|
#define YYSTYPE YYSTYPE // workaround a bug in Bison 2.4
|
|
|
|
#include "nixexpr.hh"
|
|
#include "nixexpr-ast.hh"
|
|
|
|
|
|
using namespace nix;
|
|
|
|
|
|
namespace nix {
|
|
|
|
|
|
struct ParseData
|
|
{
|
|
Expr result;
|
|
Path basePath;
|
|
Path path;
|
|
string error;
|
|
};
|
|
|
|
|
|
static string showAttrPath(ATermList attrPath)
|
|
{
|
|
string s;
|
|
for (ATermIterator i(attrPath); i; ++i) {
|
|
if (!s.empty()) s += '.';
|
|
s += aterm2String(*i);
|
|
}
|
|
return s;
|
|
}
|
|
|
|
|
|
struct Tree
|
|
{
|
|
Expr leaf; ATerm pos; bool recursive;
|
|
typedef std::map<ATerm, Tree> Children;
|
|
Children children;
|
|
Tree() { leaf = 0; recursive = true; }
|
|
};
|
|
|
|
|
|
static ATermList buildAttrs(const Tree & t, ATermList & nonrec)
|
|
{
|
|
ATermList res = ATempty;
|
|
for (Tree::Children::const_reverse_iterator i = t.children.rbegin();
|
|
i != t.children.rend(); ++i)
|
|
if (!i->second.recursive)
|
|
nonrec = ATinsert(nonrec, makeBind(i->first, i->second.leaf, i->second.pos));
|
|
else
|
|
res = ATinsert(res, i->second.leaf
|
|
? makeBind(i->first, i->second.leaf, i->second.pos)
|
|
: makeBind(i->first, makeAttrs(buildAttrs(i->second, nonrec)), makeNoPos()));
|
|
return res;
|
|
}
|
|
|
|
|
|
static Expr fixAttrs(bool recursive, ATermList as)
|
|
{
|
|
Tree attrs;
|
|
|
|
/* This ATermMap is needed to ensure that the `leaf' fields in the
|
|
Tree nodes are not garbage collected. */
|
|
ATermMap gcRoots;
|
|
|
|
for (ATermIterator i(as); i; ++i) {
|
|
ATermList names, attrPath; Expr src, e; ATerm name, pos;
|
|
|
|
if (matchInherit(*i, src, names, pos)) {
|
|
bool fromScope = matchScope(src);
|
|
for (ATermIterator j(names); j; ++j) {
|
|
if (attrs.children.find(*j) != attrs.children.end())
|
|
throw ParseError(format("duplicate definition of attribute `%1%' at %2%")
|
|
% showAttrPath(ATmakeList1(*j)) % showPos(pos));
|
|
Tree & t(attrs.children[*j]);
|
|
Expr leaf = fromScope ? makeVar(*j) : makeSelect(src, *j);
|
|
gcRoots.set(leaf, leaf);
|
|
t.leaf = leaf;
|
|
t.pos = pos;
|
|
if (recursive && fromScope) t.recursive = false;
|
|
}
|
|
}
|
|
|
|
else if (matchBindAttrPath(*i, attrPath, e, pos)) {
|
|
|
|
Tree * t(&attrs);
|
|
|
|
for (ATermIterator j(attrPath); j; ) {
|
|
name = *j; ++j;
|
|
if (t->leaf) throw ParseError(format("attribute set containing `%1%' at %2% already defined at %3%")
|
|
% showAttrPath(attrPath) % showPos(pos) % showPos (t->pos));
|
|
t = &(t->children[name]);
|
|
}
|
|
|
|
if (t->leaf)
|
|
throw ParseError(format("duplicate definition of attribute `%1%' at %2% and %3%")
|
|
% showAttrPath(attrPath) % showPos(pos) % showPos (t->pos));
|
|
if (!t->children.empty())
|
|
throw ParseError(format("duplicate definition of attribute `%1%' at %2%")
|
|
% showAttrPath(attrPath) % showPos(pos));
|
|
|
|
t->leaf = e; t->pos = pos;
|
|
}
|
|
|
|
else abort(); /* can't happen */
|
|
}
|
|
|
|
ATermList nonrec = ATempty;
|
|
ATermList rec = buildAttrs(attrs, nonrec);
|
|
|
|
return recursive ? makeRec(rec, nonrec) : makeAttrs(rec);
|
|
}
|
|
|
|
|
|
static void checkPatternVars(ATerm pos, ATermMap & map, Pattern pat)
|
|
{
|
|
ATerm name = sNoAlias;
|
|
ATermList formals;
|
|
ATermBool ellipsis;
|
|
|
|
if (matchAttrsPat(pat, formals, ellipsis, name)) {
|
|
for (ATermIterator i(formals); i; ++i) {
|
|
ATerm d1, name2;
|
|
if (!matchFormal(*i, name2, d1)) abort();
|
|
if (map.get(name2))
|
|
throw ParseError(format("duplicate formal function argument `%1%' at %2%")
|
|
% aterm2String(name2) % showPos(pos));
|
|
map.set(name2, name2);
|
|
}
|
|
}
|
|
|
|
else matchVarPat(pat, name);
|
|
|
|
if (name != sNoAlias) {
|
|
if (map.get(name))
|
|
throw ParseError(format("duplicate formal function argument `%1%' at %2%")
|
|
% aterm2String(name) % showPos(pos));
|
|
map.set(name, name);
|
|
}
|
|
}
|
|
|
|
|
|
static void checkPatternVars(ATerm pos, Pattern pat)
|
|
{
|
|
ATermMap map;
|
|
checkPatternVars(pos, map, pat);
|
|
}
|
|
|
|
|
|
static Expr stripIndentation(ATermList es)
|
|
{
|
|
if (es == ATempty) return makeStr("");
|
|
|
|
/* Figure out the minimum indentation. Note that by design
|
|
whitespace-only final lines are not taken into account. (So
|
|
the " " in "\n ''" is ignored, but the " " in "\n foo''" is.) */
|
|
bool atStartOfLine = true; /* = seen only whitespace in the current line */
|
|
unsigned int minIndent = 1000000;
|
|
unsigned int curIndent = 0;
|
|
ATerm e;
|
|
for (ATermIterator i(es); i; ++i) {
|
|
if (!matchIndStr(*i, e)) {
|
|
/* Anti-quotations end the current start-of-line whitespace. */
|
|
if (atStartOfLine) {
|
|
atStartOfLine = false;
|
|
if (curIndent < minIndent) minIndent = curIndent;
|
|
}
|
|
continue;
|
|
}
|
|
string s = aterm2String(e);
|
|
for (unsigned int j = 0; j < s.size(); ++j) {
|
|
if (atStartOfLine) {
|
|
if (s[j] == ' ')
|
|
curIndent++;
|
|
else if (s[j] == '\n') {
|
|
/* Empty line, doesn't influence minimum
|
|
indentation. */
|
|
curIndent = 0;
|
|
} else {
|
|
atStartOfLine = false;
|
|
if (curIndent < minIndent) minIndent = curIndent;
|
|
}
|
|
} else if (s[j] == '\n') {
|
|
atStartOfLine = true;
|
|
curIndent = 0;
|
|
}
|
|
}
|
|
}
|
|
|
|
/* Strip spaces from each line. */
|
|
ATermList es2 = ATempty;
|
|
atStartOfLine = true;
|
|
unsigned int curDropped = 0;
|
|
unsigned int n = ATgetLength(es);
|
|
for (ATermIterator i(es); i; ++i, --n) {
|
|
if (!matchIndStr(*i, e)) {
|
|
atStartOfLine = false;
|
|
curDropped = 0;
|
|
es2 = ATinsert(es2, *i);
|
|
continue;
|
|
}
|
|
|
|
string s = aterm2String(e);
|
|
string s2;
|
|
for (unsigned int j = 0; j < s.size(); ++j) {
|
|
if (atStartOfLine) {
|
|
if (s[j] == ' ') {
|
|
if (curDropped++ >= minIndent)
|
|
s2 += s[j];
|
|
}
|
|
else if (s[j] == '\n') {
|
|
curDropped = 0;
|
|
s2 += s[j];
|
|
} else {
|
|
atStartOfLine = false;
|
|
curDropped = 0;
|
|
s2 += s[j];
|
|
}
|
|
} else {
|
|
s2 += s[j];
|
|
if (s[j] == '\n') atStartOfLine = true;
|
|
}
|
|
}
|
|
|
|
/* Remove the last line if it is empty and consists only of
|
|
spaces. */
|
|
if (n == 1) {
|
|
string::size_type p = s2.find_last_of('\n');
|
|
if (p != string::npos && s2.find_first_not_of(' ', p + 1) == string::npos)
|
|
s2 = string(s2, 0, p + 1);
|
|
}
|
|
|
|
es2 = ATinsert(es2, makeStr(s2));
|
|
}
|
|
|
|
return makeConcatStrings(ATreverse(es2));
|
|
}
|
|
|
|
|
|
void backToString(yyscan_t scanner);
|
|
void backToIndString(yyscan_t scanner);
|
|
|
|
|
|
static Pos makeCurPos(YYLTYPE * loc, ParseData * data)
|
|
{
|
|
return makePos(toATerm(data->path),
|
|
loc->first_line, loc->first_column);
|
|
}
|
|
|
|
#define CUR_POS makeCurPos(yylocp, data)
|
|
|
|
|
|
}
|
|
|
|
|
|
void yyerror(YYLTYPE * loc, yyscan_t scanner, ParseData * data, const char * error)
|
|
{
|
|
data->error = (format("%1%, at `%2%':%3%:%4%")
|
|
% error % data->path % loc->first_line % loc->first_column).str();
|
|
}
|
|
|
|
|
|
/* Make sure that the parse stack is scanned by the ATerm garbage
|
|
collector. */
|
|
static void * mallocAndProtect(size_t size)
|
|
{
|
|
void * p = malloc(size);
|
|
if (p) ATprotectMemory(p, size);
|
|
return p;
|
|
}
|
|
|
|
static void freeAndUnprotect(void * p)
|
|
{
|
|
ATunprotectMemory(p);
|
|
free(p);
|
|
}
|
|
|
|
#define YYMALLOC mallocAndProtect
|
|
#define YYFREE freeAndUnprotect
|
|
|
|
|
|
#endif
|
|
|
|
|
|
%}
|
|
|
|
%union {
|
|
ATerm t;
|
|
ATermList ts;
|
|
struct {
|
|
ATermList formals;
|
|
bool ellipsis;
|
|
} formals;
|
|
int n;
|
|
}
|
|
|
|
%type <t> start expr expr_function expr_if expr_op
|
|
%type <t> expr_app expr_select expr_simple bind inheritsrc formal
|
|
%type <t> pattern
|
|
%type <ts> binds ids attrpath expr_list string_parts ind_string_parts
|
|
%type <formals> formals
|
|
%token <t> ID STR IND_STR PATH URI
|
|
%token <n> INT
|
|
%token IF THEN ELSE ASSERT WITH LET IN REC INHERIT EQ NEQ AND OR IMPL
|
|
%token DOLLAR_CURLY /* == ${ */
|
|
%token IND_STRING_OPEN IND_STRING_CLOSE
|
|
%token ELLIPSIS
|
|
|
|
%nonassoc IMPL
|
|
%left OR
|
|
%left AND
|
|
%nonassoc EQ NEQ
|
|
%right UPDATE
|
|
%left NEG
|
|
%left '+'
|
|
%right CONCAT
|
|
%nonassoc '?'
|
|
%nonassoc '~'
|
|
|
|
%%
|
|
|
|
start: expr { data->result = $1; };
|
|
|
|
expr: expr_function;
|
|
|
|
expr_function
|
|
: pattern ':' expr_function
|
|
{ checkPatternVars(CUR_POS, $1); $$ = makeFunction($1, $3, CUR_POS); }
|
|
| ASSERT expr ';' expr_function
|
|
{ $$ = makeAssert($2, $4, CUR_POS); }
|
|
| WITH expr ';' expr_function
|
|
{ $$ = makeWith($2, $4, CUR_POS); }
|
|
| LET binds IN expr_function
|
|
{ $$ = makeSelect(fixAttrs(true, ATinsert($2, makeBindAttrPath(ATmakeList1(toATerm("<let-body>")), $4, CUR_POS))), toATerm("<let-body>")); }
|
|
| expr_if
|
|
;
|
|
|
|
expr_if
|
|
: IF expr THEN expr ELSE expr
|
|
{ $$ = makeIf($2, $4, $6); }
|
|
| expr_op
|
|
;
|
|
|
|
expr_op
|
|
: '!' expr_op %prec NEG { $$ = makeOpNot($2); }
|
|
| expr_op EQ expr_op { $$ = makeOpEq($1, $3); }
|
|
| expr_op NEQ expr_op { $$ = makeOpNEq($1, $3); }
|
|
| expr_op AND expr_op { $$ = makeOpAnd($1, $3); }
|
|
| expr_op OR expr_op { $$ = makeOpOr($1, $3); }
|
|
| expr_op IMPL expr_op { $$ = makeOpImpl($1, $3); }
|
|
| expr_op UPDATE expr_op { $$ = makeOpUpdate($1, $3); }
|
|
| expr_op '?' ID { $$ = makeOpHasAttr($1, $3); }
|
|
| expr_op '+' expr_op { $$ = makeConcatStrings(ATmakeList2($1, $3)); }
|
|
| expr_op CONCAT expr_op { $$ = makeOpConcat($1, $3); }
|
|
| expr_app
|
|
;
|
|
|
|
expr_app
|
|
: expr_app expr_select
|
|
{ $$ = makeCall($1, $2); }
|
|
| expr_select { $$ = $1; }
|
|
;
|
|
|
|
expr_select
|
|
: expr_select '.' ID
|
|
{ $$ = makeSelect($1, $3); }
|
|
| expr_simple { $$ = $1; }
|
|
;
|
|
|
|
expr_simple
|
|
: ID { $$ = makeVar($1); }
|
|
| INT { $$ = makeInt($1); }
|
|
| '"' string_parts '"' {
|
|
/* For efficiency, and to simplify parse trees a bit. */
|
|
if ($2 == ATempty) $$ = makeStr(toATerm(""), ATempty);
|
|
else if (ATgetNext($2) == ATempty) $$ = ATgetFirst($2);
|
|
else $$ = makeConcatStrings(ATreverse($2));
|
|
}
|
|
| IND_STRING_OPEN ind_string_parts IND_STRING_CLOSE {
|
|
$$ = stripIndentation(ATreverse($2));
|
|
}
|
|
| PATH { $$ = makePath(toATerm(absPath(aterm2String($1), data->basePath))); }
|
|
| URI { $$ = makeStr($1, ATempty); }
|
|
| '(' expr ')' { $$ = $2; }
|
|
/* Let expressions `let {..., body = ...}' are just desugared
|
|
into `(rec {..., body = ...}).body'. */
|
|
| LET '{' binds '}'
|
|
{ $$ = makeSelect(fixAttrs(true, $3), toATerm("body")); }
|
|
| REC '{' binds '}'
|
|
{ $$ = fixAttrs(true, $3); }
|
|
| '{' binds '}'
|
|
{ $$ = fixAttrs(false, $2); }
|
|
| '[' expr_list ']' { $$ = makeList(ATreverse($2)); }
|
|
;
|
|
|
|
string_parts
|
|
: string_parts STR { $$ = ATinsert($1, $2); }
|
|
| string_parts DOLLAR_CURLY expr '}' { backToString(scanner); $$ = ATinsert($1, $3); }
|
|
| { $$ = ATempty; }
|
|
;
|
|
|
|
ind_string_parts
|
|
: ind_string_parts IND_STR { $$ = ATinsert($1, $2); }
|
|
| ind_string_parts DOLLAR_CURLY expr '}' { backToIndString(scanner); $$ = ATinsert($1, $3); }
|
|
| { $$ = ATempty; }
|
|
;
|
|
|
|
pattern
|
|
: ID { $$ = makeVarPat($1); }
|
|
| '{' formals '}' { $$ = makeAttrsPat($2.formals, $2.ellipsis ? eTrue : eFalse, sNoAlias); }
|
|
| '{' formals '}' '@' ID { $$ = makeAttrsPat($2.formals, $2.ellipsis ? eTrue : eFalse, $5); }
|
|
| ID '@' '{' formals '}' { $$ = makeAttrsPat($4.formals, $4.ellipsis ? eTrue : eFalse, $1); }
|
|
;
|
|
|
|
binds
|
|
: binds bind { $$ = ATinsert($1, $2); }
|
|
| { $$ = ATempty; }
|
|
;
|
|
|
|
bind
|
|
: attrpath '=' expr ';'
|
|
{ $$ = makeBindAttrPath(ATreverse($1), $3, CUR_POS); }
|
|
| INHERIT inheritsrc ids ';'
|
|
{ $$ = makeInherit($2, $3, CUR_POS); }
|
|
;
|
|
|
|
inheritsrc
|
|
: '(' expr ')' { $$ = $2; }
|
|
| { $$ = makeScope(); }
|
|
;
|
|
|
|
ids: ids ID { $$ = ATinsert($1, $2); } | { $$ = ATempty; };
|
|
|
|
attrpath
|
|
: attrpath '.' ID { $$ = ATinsert($1, $3); }
|
|
| ID { $$ = ATmakeList1($1); }
|
|
;
|
|
|
|
expr_list
|
|
: expr_list expr_select { $$ = ATinsert($1, $2); }
|
|
| { $$ = ATempty; }
|
|
;
|
|
|
|
formals
|
|
: formal ',' formals /* !!! right recursive */
|
|
{ $$.formals = ATinsert($3.formals, $1); $$.ellipsis = $3.ellipsis; }
|
|
| formal
|
|
{ $$.formals = ATinsert(ATempty, $1); $$.ellipsis = false; }
|
|
|
|
|
{ $$.formals = ATempty; $$.ellipsis = false; }
|
|
| ELLIPSIS
|
|
{ $$.formals = ATempty; $$.ellipsis = true; }
|
|
;
|
|
|
|
formal
|
|
: ID { $$ = makeFormal($1, makeNoDefaultValue()); }
|
|
| ID '?' expr { $$ = makeFormal($1, makeDefaultValue($3)); }
|
|
;
|
|
|
|
%%
|
|
|
|
|
|
#include "eval.hh"
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/stat.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
|
|
|
|
namespace nix {
|
|
|
|
|
|
static Expr parse(EvalState & state,
|
|
const char * text, const Path & path,
|
|
const Path & basePath)
|
|
{
|
|
yyscan_t scanner;
|
|
ParseData data;
|
|
data.basePath = basePath;
|
|
data.path = path;
|
|
|
|
yylex_init(&scanner);
|
|
yy_scan_string(text, scanner);
|
|
int res = yyparse(scanner, &data);
|
|
yylex_destroy(scanner);
|
|
|
|
if (res) throw ParseError(data.error);
|
|
|
|
try {
|
|
// !!! checkVarDefs(state.primOps, data.result);
|
|
} catch (Error & e) {
|
|
throw ParseError(format("%1%, in `%2%'") % e.msg() % path);
|
|
}
|
|
|
|
return data.result;
|
|
}
|
|
|
|
|
|
Expr parseExprFromFile(EvalState & state, Path path)
|
|
{
|
|
assert(path[0] == '/');
|
|
|
|
/* If `path' is a symlink, follow it. This is so that relative
|
|
path references work. */
|
|
struct stat st;
|
|
while (true) {
|
|
if (lstat(path.c_str(), &st))
|
|
throw SysError(format("getting status of `%1%'") % path);
|
|
if (!S_ISLNK(st.st_mode)) break;
|
|
path = absPath(readLink(path), dirOf(path));
|
|
}
|
|
|
|
/* If `path' refers to a directory, append `/default.nix'. */
|
|
if (stat(path.c_str(), &st))
|
|
throw SysError(format("getting status of `%1%'") % path);
|
|
if (S_ISDIR(st.st_mode))
|
|
path = canonPath(path + "/default.nix");
|
|
|
|
/* Read and parse the input file. */
|
|
return parse(state, readFile(path).c_str(), path, dirOf(path));
|
|
}
|
|
|
|
|
|
Expr parseExprFromString(EvalState & state,
|
|
const string & s, const Path & basePath)
|
|
{
|
|
return parse(state, s.c_str(), "(string)", basePath);
|
|
}
|
|
|
|
|
|
}
|