diff options
| -rw-r--r-- | src/libexpr/eval.cc | 10 | ||||
| -rw-r--r-- | src/libexpr/lexer.l | 41 | ||||
| -rw-r--r-- | src/libexpr/nixexpr-ast.def | 1 | ||||
| -rw-r--r-- | src/libexpr/parser.cc | 22 | ||||
| -rw-r--r-- | src/libexpr/parser.y | 17 | ||||
| -rw-r--r-- | tests/lang/eval-okay-string.exp | 2 | ||||
| -rw-r--r-- | tests/lang/eval-okay-string.nix | 10 |
7 files changed, 88 insertions, 15 deletions
diff --git a/src/libexpr/eval.cc b/src/libexpr/eval.cc index 1c2aafd91f..d70ac9f76a 100644 --- a/src/libexpr/eval.cc +++ b/src/libexpr/eval.cc @@ -231,7 +231,7 @@ static ATerm concatStrings(EvalState & state, const ATermVector & args) { ATermList context = ATempty; ostringstream s; - bool isPath; + bool isPath = false; for (ATermVector::const_iterator i = args.begin(); i != args.end(); ++i) { bool isPath2; @@ -449,6 +449,14 @@ Expr evalExpr2(EvalState & state, Expr e) return makeList(ATconcat(l1, l2)); } + /* String concatenation. */ + ATermList es; + if (matchConcatStrings(e, es)) { + ATermVector args; + for (ATermIterator i(es); i; ++i) args.push_back(*i); + return concatStrings(state, args); + } + /* Barf. */ throw badTerm("invalid expression", e); } diff --git a/src/libexpr/lexer.l b/src/libexpr/lexer.l index d5a14f517a..47f2bca1e6 100644 --- a/src/libexpr/lexer.l +++ b/src/libexpr/lexer.l @@ -3,6 +3,9 @@ %option never-interactive +%x STRING + + %{ #include <string.h> #include <aterm2.h> @@ -28,6 +31,9 @@ static void adjustLoc(YYLTYPE * loc, const char * s, size_t len) } } +ATerm toATerm(const char * s); +ATerm unescapeStr(const char * s); + #define YY_USER_INIT initLoc(yylloc) #define YY_USER_ACTION adjustLoc(yylloc, yytext, yyleng); @@ -36,7 +42,6 @@ static void adjustLoc(YYLTYPE * loc, const char * s, size_t len) ID [a-zA-Z\_][a-zA-Z0-9\_\']* INT [0-9]+ -STR \"[^\n\"]*\" PATH [a-zA-Z0-9\.\_\-\+]*(\/[a-zA-Z0-9\.\_\-\+]+)+ URI [a-zA-Z][a-zA-Z0-9\+\-\.]*\:[a-zA-Z0-9\%\/\?\:\@\&\=\+\$\,\-\_\.\!\~\*\']+ @@ -61,19 +66,27 @@ inherit { return INHERIT; } \/\/ { return UPDATE; } \+\+ { return CONCAT; } -{ID} { yylval->t = ATmake("<str>", yytext); return ID; /* !!! alloc */ } +{ID} { yylval->t = toATerm(yytext); return ID; /* !!! alloc */ } {INT} { int n = atoi(yytext); /* !!! overflow */ yylval->t = ATmake("<int>", n); return INT; } -{STR} { int len = strlen(yytext); - yytext[len - 1] = 0; - yylval->t = ATmake("<str>", yytext + 1); - yytext[len - 1] = '\"'; - return STR; /* !!! alloc */ + +\" { BEGIN(STRING); return '"'; } +<STRING>([^\$\"\\]|\\.|\$[^\{\$])+ { +/* Note: a dollar *is* allowed as-is in a string, as long as it's + not followed by a open brace. This should probably be disallowed + eventually. */ + yylval->t = unescapeStr(yytext); /* !!! alloc */ + return STR; } -{PATH} { yylval->t = ATmake("<str>", yytext); return PATH; /* !!! alloc */ } -{URI} { yylval->t = ATmake("<str>", yytext); return URI; /* !!! alloc */ } +<STRING>\$\{ { BEGIN(INITIAL); return DOLLAR_CURLY; } +<STRING>\" { BEGIN(INITIAL); return '"'; } +<STRING>. return yytext[0]; /* just in case: shouldn't be reached */ + + +{PATH} { yylval->t = toATerm(yytext); return PATH; /* !!! alloc */ } +{URI} { yylval->t = toATerm(yytext); return URI; /* !!! alloc */ } [ \t\n]+ /* eat up whitespace */ \#[^\n]* /* single-line comments */ @@ -83,3 +96,13 @@ inherit { return INHERIT; } %% + +/* Horrible, disgusting hack: allow the parser to set the scanner + start condition back to STRING. Necessary in interpolations like + "foo${expr}bar"; after the close brace we have to go back to the + STRING state. */ +void backToString(yyscan_t scanner) +{ + struct yyguts_t * yyg = (struct yyguts_t*) scanner; + BEGIN(STRING); +} diff --git a/src/libexpr/nixexpr-ast.def b/src/libexpr/nixexpr-ast.def index fab560c99f..3f6473e940 100644 --- a/src/libexpr/nixexpr-ast.def +++ b/src/libexpr/nixexpr-ast.def @@ -19,6 +19,7 @@ SubPath | Expr Expr | Expr | OpHasAttr | Expr string | Expr | OpPlus | Expr Expr | Expr | OpConcat | Expr Expr | Expr | +ConcatStrings | ATermList | Expr | Call | Expr Expr | Expr | Select | Expr string | Expr | Var | string | Expr | diff --git a/src/libexpr/parser.cc b/src/libexpr/parser.cc index 16b94fa62c..2ca1cab4af 100644 --- a/src/libexpr/parser.cc +++ b/src/libexpr/parser.cc @@ -71,9 +71,29 @@ const char * getPath(ParseData * data) return data->path.c_str(); } -int yyparse(yyscan_t scanner, ParseData * data); +Expr unescapeStr(const char * s) +{ + string t; + char c; + while (c = *s++) { + if (c == '\\') { + assert(*s); + c = *s++; + if (c == 'n') t += "\n"; + else if (c == 'r') t += "\r"; + else if (c == 't') t += "\t"; + else t += c; + } + else t += c; + } + return makeStr(toATerm(t)); } +int yyparse(yyscan_t scanner, ParseData * data); + + +} /* end of C functions */ + static void checkAttrs(ATermMap & names, ATermList bnds) { diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y index ec07a01919..cba390d8da 100644 --- a/src/libexpr/parser.y +++ b/src/libexpr/parser.y @@ -25,6 +25,7 @@ void parseError(void * data, char * error, int line, int column); ATerm absParsedPath(void * data, ATerm t); ATerm fixAttrs(int recursive, ATermList as); const char * getPath(void * data); +void backToString(yyscan_t scanner); void yyerror(YYLTYPE * loc, yyscan_t scanner, void * data, char * s) { @@ -73,9 +74,10 @@ static void freeAndUnprotect(void * p) %type <t> start expr expr_function expr_if expr_op %type <t> expr_app expr_select expr_simple bind inheritsrc formal -%type <ts> binds ids expr_list formals +%type <ts> binds ids expr_list formals string_parts %token <t> ID INT STR PATH URI %token IF THEN ELSE ASSERT WITH LET REC INHERIT EQ NEQ AND OR IMPL +%token DOLLAR_CURLY /* == ${ */ %nonassoc IMPL %left OR @@ -142,7 +144,12 @@ expr_select expr_simple : ID { $$ = makeVar($1); } | INT { $$ = makeInt(ATgetInt((ATermInt) $1)); } - | STR { $$ = makeStr($1); } + | '"' string_parts '"' { + /* For efficiency, and to simplify parse trees a bit. */ + if ($2 == ATempty) $$ = makeStr(toATerm("")); + else if (ATgetNext($2) == ATempty) $$ = ATgetFirst($2); + else $$ = makeConcatStrings(ATreverse($2)); + } | PATH { $$ = makePath(absParsedPath(data, $1)); } | URI { $$ = makeUri($1); } | '(' expr ')' { $$ = $2; } @@ -157,6 +164,12 @@ expr_simple | '[' expr_list ']' { $$ = makeList($2); } ; +string_parts + : string_parts STR { $$ = ATinsert($1, $2); } + | string_parts DOLLAR_CURLY expr '}' { backToString(scanner); $$ = ATinsert($1, $3); } + | { $$ = ATempty; } + ; + binds : binds bind { $$ = ATinsert($1, $2); } | { $$ = ATempty; } diff --git a/tests/lang/eval-okay-string.exp b/tests/lang/eval-okay-string.exp index 9c3f56c3f3..dd0e5e248d 100644 --- a/tests/lang/eval-okay-string.exp +++ b/tests/lang/eval-okay-string.exp @@ -1 +1 @@ -Str("foobar/a/b/c/d/foo/xyzzy/foo.txt/../foo/x/y") +Str("foobar/a/b/c/d/foo/xyzzy/foo.txt/../foo/x/yescape: \"quote\" \n \\end\nof\nlinefoobarblaat") diff --git a/tests/lang/eval-okay-string.nix b/tests/lang/eval-okay-string.nix index b5280a0cd1..f2452e8574 100644 --- a/tests/lang/eval-okay-string.nix +++ b/tests/lang/eval-okay-string.nix @@ -1 +1,9 @@ -"foo" + "bar" + toString (/a/b + /c/d) + (/foo/bar + "/../xyzzy/." + "/foo.txt") + ("/../foo" + /x/y) +"foo" + "bar" + + toString (/a/b + /c/d) + + (/foo/bar + "/../xyzzy/." + "/foo.txt") + + ("/../foo" + /x/y) + + "escape: \"quote\" \n \\" + + "end +of +line" + + "foo${if true then "b${"a" + "r"}" else "xyzzy"}blaat" |