Recomendar C front-end que conserva las directivas de preprocesador

Question

que me gustaría empezar un proyecto que consiste en la transformación de C código, pero me gustaría incluyen las directivas del preprocesador. No quiero reinventar la rueda escribiendo mi propia C analizador, así que ¿alguien sabe de un front-end que puede analizar C preprocesador y código C, y producir un AST que se puede utilizar para volver -generar (o imprimir bastante) la fuente original?

por ejemplo,:.

#define FILENAME "filename" 
#include <stdio.h> 

FILE *f=0; 
... 
if (file_is_open) { 
#ifdef CAN_OPEN_IT 
    f = fopen(FILENAME, "r"); 
#else 
    printf("Unable to open file.\n"); 
#endif 
} 

El código anterior debe ser analizado en alguna representación en memoria que se puede utilizar para volver a generar la fuente. En otras palabras, no se debe procesar como normal C en dos fases, primero procesando las directivas PP y luego analizando el código puro C. Más bien debería representar toda la lógica del tiempo de compilación, incluidas las variables del preprocesador.

Answer 1

Eche un vistazo a Clang. (Ver http://clang.llvm.org/features.html#applications.)

Answer 2

Tome el compilador GNU gcc, los indicadores necesarios para preprocesar la fuente son gcc -E mysource.c, consulte here para obtener más información. En cuanto a la impresión bonita, hay indent y esto explica el uso here, esto es un poco viejo, pero no obstante vale la pena mencionarlo. También hay cflow que puede producir un mapa de la fuente.

Lo siento si no he entendido bien lo que estás buscando ...

Espero que esto ayude, Saludos, Tom.

Answer 3

Puede tomar mirar el http://www.antlr.org/wiki/display/ANTLR3/ANTLR3+Code+Generation+-+C

Answer 4

Nuestra DMS Software Reengineering Toolkit tiene a C front end (y extremo frontal de C++) que:

• análisis sintácticos (compilables) de código fuente de C en una variedad de dialectos en AST,
• conserva las directivas del preprocesador en la mayoría de los casos como nodos AST
• puede regenerar código C compilable (con comentarios y directivas de preprocesador) de la AST s
• se recoge miles de archivos en una sola imagen para permitir el análisis entre archivos y transformación
• proporciona plena construcción de la tabla de símbolos y el acceso
• proporciona acceso procedimental y AST con una gran biblioteca de manipulación de AST, incluyendo la navegación, para inspeccionar , insertar, eliminar, reemplazar, unir, ...
• proporciona transformaciones de fuente a fuente utilizando patrones escritos en la notación C que responden contra los ASTs

Para C (todavía no para C++), DMS también proporciona:

• de control y datos análisis de flujo
• puntos-a locales y globales análisis
• construcción gráfica de llamada global

DMS se ha utilizado para procesar aplicaciones C extremadamente grandes con el fin de extraer hechos y generar código nuevo y derivado de la base de la fuente original.

(EDIT: Feb 2016)

Puede manejar el ejemplo de la OP (con ligeras correcciones para que sea válido). Aquí está la fuente ligeramente revisada:

#define FILENAME "filename" 
#include <stdio.h> 

FILE *f; 
main() { 
    f=0; 
if (file_is_open) { 
#ifdef CAN_OPEN_IT 
f = fopen(FILENAME, "r"); 
#else 
printf("Unable to open file.\n"); 
#endif 
} 

} 

Aquí es el AST producido:

C~GCC4 Domain Parser Version 3.0.1(28449) 
Copyright (C) 1996-2013 Semantic Designs, Inc; All Rights Reserved; SD Confidential 
Powered by DMS (R) Software Reengineering Toolkit 
AST Optimizations: remove constant tokens, remove unary productions, compact sequences 
Using encoding Unicode-UTF-8?ANSI +CRLF +1 /^I 
(translation_unit@C~GCC4=2#4a7e0e0^0 Line 1 Column 1 File C:/temp/test.c 
(declaration_seq@C~GCC4=605#4a77580^1#4a7e0e0:1 {4} Line 1 Column 1 File C:/temp/test.c 
    (control_line@C~GCC4=1094#4a775c0^1#4a77580:1 Line 1 Column 1 File C:/temp/test.c 
    ('#'@C~GCC4=1548#4a771c0^1#4a775c0:1[Keyword:0] Line 1 Column 1 File C:/temp/test.c)'#' 
    (IDENTIFIER@C~GCC4=1531#4a77200^1#4a775c0:2[`FILENAME'] Line 1 Column 9 File C:/temp/test.c)IDENTIFIER 
    (<!MacroDefinition>@C~GCC4=1603#4a77180^2#4a775c0:3#4a7f300:1[`FILENAME'] Line 1 Column 18 File C:/temp/test.c 
$VOID$ [Child 1] 
    |(STRING_LITERAL@C~GCC4=1525#4a77160^2#4a77180:2#4a7f300:2[`filename'] Line 1 Column 18 File C:/temp/test.c)STRING_LITERAL 
$VOID$ [Child 3] 
    )<!MacroDefinition>#4a77180 
    (new_line@C~GCC4=1578#4a77260^1#4a775c0:4[Keyword:0] Line 1 Column 28 File C:/temp/test.c)new_line 
)control_line#4a775c0 
    (control_line@C~GCC4=1104#4a77460^1#4a77580:2 Line 2 Column 1 File C:/temp/test.c 
    ('#'@C~GCC4=1548#4a77340^1#4a77460:1[Keyword:0] Line 2 Column 1 File C:/temp/test.c)'#' 
    (ANGLED_HEADER_NAME@C~GCC4=1589#4a77380^1#4a77460:2[`stdio.h'] Line 2 Column 10 File C:/temp/test.c)ANGLED_HEADER_NAME 
    (new_line@C~GCC4=1578#4a773c0^1#4a77460:3[Keyword:0] Line 2 Column 19 File C:/temp/test.c)new_line 
)control_line#4a77460 
    (simple_declaration@C~GCC4=631#4a774c0^1#4a77580:3 Line 4 Column 1 File C:/temp/test.c 
    (IDENTIFIER@C~GCC4=1531#4a77360^1#4a774c0:1[`FILE'] Line 4 Column 1 File C:/temp/test.c)IDENTIFIER 
    (declarator@C~GCC4=850#4a77520^1#4a774c0:2 Line 4 Column 6 File C:/temp/test.c 
    |(ptr_operator@C~GCC4=866#4a77560^1#4a77520:1 Line 4 Column 6 File C:/temp/test.c)ptr_operator 
    |(IDENTIFIER@C~GCC4=1531#4a77480^1#4a77520:2[`f'] Line 4 Column 7 File C:/temp/test.c)IDENTIFIER 
    )declarator#4a77520 
)simple_declaration#4a774c0 
    (function_definition@C~GCC4=966#4a77be0^1#4a77580:4 Line 5 Column 1 File C:/temp/test.c 
    (direct_declarator@C~GCC4=852#4a77440^1#4a77be0:1 Line 5 Column 1 File C:/temp/test.c 
    |(IDENTIFIER@C~GCC4=1531#4a774e0^1#4a77440:1[`main'] Line 5 Column 1 File C:/temp/test.c)IDENTIFIER 
    |(parameter_declaration_clause@C~GCC4=900#4a77220^1#4a77440:2 Line 5 Column 6 File C:/temp/test.c)parameter_declaration_clause 
    )direct_declarator#4a77440 
    (compound_statement@C~GCC4=507#4a77b20^1#4a77be0:2 Line 5 Column 8 File C:/temp/test.c 
    |(statement_seq@C~GCC4=511#4a77d20^1#4a77b20:1 {2} Line 6 Column 3 File C:/temp/test.c 
    | (AMBIGUITY<statement=358>@C~GCC4=1602#4a77680^1#4a77d20:1{2} Line 6 Column 3 File C:/temp/test.c 
    | (expression_statement@C~GCC4=503#4a7e040^1#4a77680:1 Line 6 Column 3 File C:/temp/test.c 
    | (assignment_expression@C~GCC4=457#4a77f00^1#4a7e040:1 Line 6 Column 3 File C:/temp/test.c 
    | |(assignment_target@C~GCC4=470#4a77a00^1#4a77f00:1 Line 6 Column 3 File C:/temp/test.c 
    | | (IDENTIFIER@C~GCC4=1531#4a77400^2#4a77a00:1#4a77fc0:1[`f'] Line 6 Column 3 File C:/temp/test.c)IDENTIFIER 
    | |)assignment_target#4a77a00 
    | |(INT_LITERAL@C~GCC4=1471#4a77a60^2#4a77f00:2#4a77f60:1[0] Line 6 Column 5 File C:/temp/test.c)INT_LITERAL 
    | )assignment_expression#4a77f00 
    | )expression_statement#4a7e040 
    | (simple_declaration@C~GCC4=630#4a7e060^1#4a77680:2 Line 6 Column 3 File C:/temp/test.c 
    | (init_declarator@C~GCC4=835#4a77fc0^1#4a7e060:1 Line 6 Column 3 File C:/temp/test.c 
    | |(IDENTIFIER@C~GCC4=1531#4a77400^2... [ALREADY PRINTED] ...) 
    | |(initializer@C~GCC4=983#4a77f60^1#4a77fc0:2 Line 6 Column 4 File C:/temp/test.c 
    | | (INT_LITERAL@C~GCC4=1471#4a77a60^2... [ALREADY PRINTED] ...) 
    | |)initializer#4a77f60 
    | )init_declarator#4a77fc0 
    | )simple_declaration#4a7e060 
    |)AMBIGUITY#4a77680 
    | (selection_statement@C~GCC4=527#4a77b40^1#4a77d20:2 Line 7 Column 1 File C:/temp/test.c 
    | (IDENTIFIER@C~GCC4=1531#4a7e0c0^1#4a77b40:1[`file_is_open'] Line 7 Column 5 File C:/temp/test.c)IDENTIFIER 
    | (compound_statement@C~GCC4=507#4a77ae0^1#4a77b40:2 Line 7 Column 19 File C:/temp/test.c 
    | (statement@C~GCC4=490#4a7f840^1#4a77ae0:1 Line 8 Column 1 File C:/temp/test.c 
    | |(if_directive@C~GCC4=1088#4a7f1c0^1#4a7f840:1 Line 8 Column 1 File C:/temp/test.c 
    | | ('#'@C~GCC4=1548#4a7f240^1#4a7f1c0:1[Keyword:0] Line 8 Column 1 File C:/temp/test.c)'#' 
    | | (IDENTIFIER@C~GCC4=1531#4a7ee60^1#4a7f1c0:2[`CAN_OPEN_IT'] Line 8 Column 8 File C:/temp/test.c)IDENTIFIER 
    | | (new_line@C~GCC4=1578#4a7f1e0^1#4a7f1c0:3[Keyword:0] Line 8 Column 19 File C:/temp/test.c)new_line 
    | |)if_directive#4a7f1c0 
    | |(AMBIGUITY<statement=358>@C~GCC4=1602#4a77d40^1#4a7f840:2{2} Line 9 Column 5 File C:/temp/test.c 
    | | (expression_statement@C~GCC4=503#4a7f4a0^1#4a77d40:1 Line 9 Column 5 File C:/temp/test.c 
    | | (assignment_expression@C~GCC4=457#4a7f3c0^1#4a7f4a0:1 Line 9 Column 5 File C:/temp/test.c 
    | | (assignment_target@C~GCC4=470#4a7eec0^1#4a7f3c0:1 Line 9 Column 5 File C:/temp/test.c 
    | | |(IDENTIFIER@C~GCC4=1531#4a7eee0^2#4a7eec0:1#4a7f400:1[`f'] Line 9 Column 5 File C:/temp/test.c)IDENTIFIER 
    | | )assignment_target#4a7eec0 
    | | (postfix_expression@C~GCC4=201#4a7f2e0^1#4a7f3c0:2 Line 9 Column 9 File C:/temp/test.c 
    | | |(IDENTIFIER@C~GCC4=1531#4a7f120^2#4a7f2e0:1#4a7f160:1[`fopen'] Line 9 Column 9 File C:/temp/test.c)IDENTIFIER 
    | | |(expression_list@C~GCC4=228#4a7f260^2#4a7f2e0:2#4a7f160:2 Line 9 Column 15 File C:/temp/test.c 
    | | | (<!MacroCall>@C~GCC4=1607#4a7f300^1#4a7f260:1[`FILENAME'] Line 9 Column 15 File C:/temp/test.c 
    | | | (<!MacroDefinition>@C~GCC4=1603#4a77180^2... [ALREADY PRINTED] ...) 
    | | | (STRING_LITERAL@C~GCC4=1525#4a77160^2... [ALREADY PRINTED] ...) 
    | | | $VOID$ [Child 3] 
    | | | (STRING_LITERAL@C~GCC4=1525#4a7f2c0^1#4a7f300:4[`filename'] Line 1 Column 18 File C:/temp/test.c)STRING_LITERAL 
    | | | $VOID$ [Child 5] 
    | | |)<!MacroCall>#4a7f300 
    | | | (STRING_LITERAL@C~GCC4=1525#4a7f140^1#4a7f260:2[`r'] Line 9 Column 25 File C:/temp/test.c)STRING_LITERAL 
    | | |)expression_list#4a7f260 
    | | )postfix_expression#4a7f2e0 
    | | )assignment_expression#4a7f3c0 
    | |)expression_statement#4a7f4a0 
    | | (simple_declaration@C~GCC4=630#4a7f480^1#4a77d40:2 Line 9 Column 5 File C:/temp/test.c 
    | | (init_declarator@C~GCC4=835#4a7f400^1#4a7f480:1 Line 9 Column 5 File C:/temp/test.c 
    | | (IDENTIFIER@C~GCC4=1531#4a7eee0^2... [ALREADY PRINTED] ...) 
    | | (initializer@C~GCC4=983#4a7f3e0^1#4a7f400:2 Line 9 Column 7 File C:/temp/test.c 
    | | |(postfix_expression@C~GCC4=201#4a7f160^1#4a7f3e0:1 Line 9 Column 9 File C:/temp/test.c 
    | | | (IDENTIFIER@C~GCC4=1531#4a7f120^2... [ALREADY PRINTED] ...) 
    | | | (expression_list@C~GCC4=228#4a7f260^2... [ALREADY PRINTED] ...) 
    | | |)postfix_expression#4a7f160 
    | | )initializer#4a7f3e0 
    | | )init_declarator#4a7f400 
    | |)simple_declaration#4a7f480 
    | |)AMBIGUITY#4a77d40 
    | |(else_directive@C~GCC4=1091#4a7f4c0^1#4a7f840:3 Line 10 Column 1 File C:/temp/test.c 
    | | ('#'@C~GCC4=1548#4a7f500^1#4a7f4c0:1[Keyword:0] Line 10 Column 1 File C:/temp/test.c)'#' 
    | | (new_line@C~GCC4=1578#4a7f4e0^1#4a7f4c0:2[Keyword:0] Line 10 Column 6 File C:/temp/test.c)new_line 
    | |)else_directive#4a7f4c0 
    | |(expression_statement@C~GCC4=503#4a7f7c0^1#4a7f840:4 Line 11 Column 5 File C:/temp/test.c 
    | | (postfix_expression@C~GCC4=201#4a77ba0^1#4a7f7c0:1 Line 11 Column 5 File C:/temp/test.c 
    | | (IDENTIFIER@C~GCC4=1531#4a7f640^1#4a77ba0:1[`printf'] Line 11 Column 5 File C:/temp/test.c)IDENTIFIER 
    | | (STRING_LITERAL@C~GCC4=1525#4a77c20^1#4a77ba0:2[`Unable to open file. 
'] Line 11 Column 12 File C:/temp/test.c)STRING_LITERAL 
    | |)postfix_expression#4a77ba0 
    | |)expression_statement#4a7f7c0 
    | |(endif_directive@C~GCC4=1092#4a7f7e0^1#4a7f840:5 Line 12 Column 1 File C:/temp/test.c 
    | | ('#'@C~GCC4=1548#4a7f720^1#4a7f7e0:1[Keyword:0] Line 12 Column 1 File C:/temp/test.c)'#' 
    | | (new_line@C~GCC4=1578#4a7f700^1#4a7f7e0:2[Keyword:0] Line 12 Column 7 File C:/temp/test.c)new_line 
    | |)endif_directive#4a7f7e0 
    | )statement#4a7f840 
    | )compound_statement#4a77ae0 
    |)selection_statement#4a77b40 
    |)statement_seq#4a77d20 
    )compound_statement#4a77b20 
)function_definition#4a77be0 
)declaration_seq#4a77580 
)translation_unit#4a7e0e0 

Puede ver las directivas del preprocesador como "if_directive" en la línea 8.

Sí, DMS puede prettyprint este árbol, también. El siguiente comando ejecuta el analizador para producir un AST y luego ejecuta la impresora bonita DMS para regenerar la fuente únicamente desde el árbol. El viaje de ida y vuelta es preciso; puedes recompilar y obtener el mismo resultado. Los comentarios se conservan también.

C:\DMS\Domains\C\GCC4\Tools\PrettyPrinter>run domainprettyprinter \temp\test.c 
C~GCC4 PrettyPrinter Version 1.2.13 
Copyright (C) 2004-2013 Semantic Designs, Inc; All Rights Reserved; SD Confidential 
Powered by DMS (R) Software Reengineering Toolkit 

#define FILENAME "filename" 
#include <stdio.h> 
FILE *f; 

main() 
{ 
    f = 0; 
    if (file_is_open) 
    { 
     #ifdef CAN_OPEN_IT 
     f = fopen(FILENAME, "r"); 
     #else 
     printf("Unable to open file.\n"); 
     #endif 
    } 
} 

You can see how DMS handles C++. En este punto maneja todos los C++ 14 para dialectos GCC y MS.