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#pragma once
#include <u.h>
#include <libn.h>
#include <errno.h>
#include <sys/wait.h>
#define alloc(ptr) ptr = emalloc(sizeof(*ptr))
// -----------------------------------------------------------------------
// main enums
#define GLOB 0x01
/* TODO: make sure there are no collisions */
enum
{
/* keywords */
Kstart=11, Kfor, Kin, Kwhile, Kif, Kelse,
Kswitch, Kcase, Kfunc, Ktwiddle,
Kbang, Ksubsh, Kend,
/* tokens */
Aword='w', Aredir='r', Adup='d', Asimple='s',
Aargs='A', Awords='W', Abrace='b', Aparen='p', Asub='S',
Apcmd='c', Apipefd='-', Aandand='%', Aoror='@', Acount='#',
Atick='`', Apipe = '|', Adol='$', Aquote='"', Aand='&',
Alparen = '(', Arparen = ')', Albrace='{', Arbrace='}',
Asemi=';', Acarot='^', Aeq='=',
};
enum
{
Rappend = 1,
Rwrite = 2,
Rread = 3,
Rhere = 4,
Rdupfd = 5,
Rclose = 6,
Rrdwr = 7,
};
// -----------------------------------------------------------------------
// main types
typedef union Code Code;
typedef struct Word Word;
typedef struct List List;
typedef struct Var Var;
typedef struct Tree Tree;
typedef struct Builtin Builtin;
typedef struct Thread Thread;
typedef struct Io Io;
union Code
{
int i;
char *s;
void (*f)(void);
};
struct Word
{
char *word;
Word *link;
};
struct List
{
Word *words;
List *link;
};
struct Var
{
string name;
Word *val;
Code *func;
Var *link;
};
struct Tree
{
ushort type;
uchar quoted : 1;
union {
char *str;
struct {
ushort type;
int fd[2];
} redir;
};
Tree *child[3], *link;
};
struct Builtin
{
char *cmd;
void (*func)(void);
};
struct Thread
{
Code *code, *ip;
List *stack;
Var *local;
struct {
uchar eof : 1;
int line;
char *name;
Io *io;
} cmd;
int pid;
Tree *nodes;
Thread *link; /* continuation */
};
struct Io
{
int fd;
uchar *b, *e, buf[];
};
// -----------------------------------------------------------------------
// global interpreter variables
extern Thread *shell;
extern int ntrap;
extern int status;
extern Io *errio;
extern Builtin builtins[];
extern Var *globals[1021]; /* for now must be prime */
// -----------------------------------------------------------------------
// interpreter functions (defined in exec.c)
/*
* notation:
* (var1, var2, ...) : items from stack
* [var1, var2, ...] : items from code stream
* -> moves value
*/
extern void Xmark(void); /* Xmark: delimit stack with new list */
extern void Xword(void); /* Xword[val] -> (val) */
extern void Xassign(void); /* Xassign(name, val): assign name to val */
extern void Xdol(void); /* Xdol(name): get variable value */
extern void Xsimple(void); /* Xsimple(args): run command */
extern void Xexit(void); /* Xexit: exit with status */
extern void Xerror(char *s); /* Xerror: report an error */
extern void Xparse(void);
// -----------------------------------------------------------------------
// shell functions
/*
* util.c
*/
void *emalloc(uintptr size);
void *erealloc(void *ptr, uintptr size);
void efree(void *);
void panic(char *msg, int n);
/*
* io.c
*/
Io *openfd(int fd);
Io *openstr(void);
Io *opencore(int len, char *s);
void rewindio(Io *f);
void closeio(Io *f);
void flush(Io **fp);
/* reads */
int rchr(Io *f);
/* writes */
int pchr(Io *f, int c);
void pquo(Io *f, char *s);
void pwrd(Io *f, char *s);
void pptr(Io *f, void *v);
void pstr(Io *f, char *s);
void pdec(Io *f, int n);
void poct(Io *f, uint n);
void pval(Io *f, Word *a);
void pcmd(Io *f, Tree *t);
void pfmt(Io *f, char *fmt, ...);
void vpfmt(Io *f, char *fmt, va_list args);
/*
* word.c
*/
void pushlist(void);
void freelist(Word *w);
void poplist(void);
int count(Word *w);
Word *newword(char *w, Word *link);
void pushword(char *w);
/*
* tree.c
*/
Tree *newtree(void);
void freetree(Tree *t);
Tree *tree3(int type, Tree *c0, Tree *c1, Tree *c2);
Tree *tree2(int type, Tree *c0, Tree *c1);
Tree *tree1(int type, Tree *c0);
Tree *hang1(Tree *p, Tree *c0);
Tree *hang2(Tree *p, Tree *c0, Tree *c1);
Tree *hang3(Tree *p, Tree *c0, Tree *c1, Tree *c2);
Tree *epihang(Tree *c, Tree *epi);
Tree *simplehang(Tree *t);
Tree *wordnode(char *w);
/*
* var.c
*/
Var *newvar(char *name, Var *link);
Var *gvlookup(char *name);
Var *vlookup(char *name);
int kwlookup(char *name);
void initkw(void);
/*
* lex.c
*/
void skipnl(void);
int wordchr(char c);
void rcerror(char *msg, ...);
int lex(Tree **node);
/*
* parse.c
*/
int parse(void);
/*
* main.c
*/
void dotrap(void);
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