/* * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ /* * lexical analysis and source input */ #include "sh.h"#include <ctype.h> /* Structure to keep track of the lexing state and the various pieces of info * needed for each particular state. */typedef struct lex_state Lex_state;struct lex_state { int ls_state; union { /* $(...) */ struct scsparen_info { int nparen; /* count open parenthesis */ int csstate; /* XXX remove */#define ls_scsparen ls_info.u_scsparen } u_scsparen; /* $((...)) */ struct sasparen_info { int nparen; /* count open parenthesis */ int start; /* marks start of $(( in output str */#define ls_sasparen ls_info.u_sasparen } u_sasparen; /* ((...)) */ struct sletparen_info { int nparen; /* count open parenthesis */#define ls_sletparen ls_info.u_sletparen } u_sletparen; /* `...` */ struct sbquote_info { int indquotes; /* true if in double quotes: "`...`" */#define ls_sbquote ls_info.u_sbquote } u_sbquote; Lex_state *base; /* used to point to next state block */ } ls_info;}; typedef struct State_info State_info;struct State_info { Lex_state *base; Lex_state *end;}; static void readhere ARGS((struct ioword *iop));static int getsc__ ARGS((void));static void getsc_line ARGS((Source *s));static int getsc_bn ARGS((void));static char *get_brace_var ARGS((XString *wsp, char *wp));static int arraysub ARGS((char **strp));static const char *ungetsc ARGS((int c));static void gethere ARGS((void));static Lex_state *push_state_ ARGS((State_info *si, Lex_state *old_end));static Lex_state *pop_state_ ARGS((State_info *si, Lex_state *old_end)); static int backslash_skip;static int ignore_backslash_newline; /* optimized getsc_bn() */#define getsc() (*source->str != '\0' && *source->str != '\\' \ && !backslash_skip ? *source->str++ : getsc_bn())/* optimized getsc__() */#define getsc_() ((*source->str != '\0') ? *source->str++ : getsc__()) #define STATE_BSIZE 32 #define PUSH_STATE(s) do { \ if (++statep == state_info.end) \ statep = push_state_(&state_info, statep); \ state = statep->ls_state = (s); \ } while (0) #define POP_STATE() do { \ if (--statep == state_info.base) \ statep = pop_state_(&state_info, statep); \ state = statep->ls_state; \ } while (0) /* * Lexical analyzer * * tokens are not regular expressions, they are LL(1). * for example, "${var:-${PWD}}", and "$(size $(whence ksh))". * hence the state stack. */ intyylex(cf) int cf;{ Lex_state states[STATE_BSIZE], *statep; State_info state_info; register int c, state; XString ws; /* expandable output word */ register char *wp; /* output word pointer */ char *sp, *dp; int c2; Again: states[0].ls_state = -1; states[0].ls_info.base = (Lex_state *) 0; statep = &states[1]; state_info.base = states; state_info.end = &states[STATE_BSIZE]; Xinit(ws, wp, 64, ATEMP); backslash_skip = 0; ignore_backslash_newline = 0; if (cf&ONEWORD) state = SWORD;#ifdef KSH else if (cf&LETEXPR) { *wp++ = OQUOTE; /* enclose arguments in (double) quotes */ state = SLETPAREN; statep->ls_sletparen.nparen = 0; }#endif /* KSH */ else { /* normal lexing */ state = (cf & HEREDELIM) ? SHEREDELIM : SBASE; while ((c = getsc()) == ' ' || c == '\t') ; if (c == '#') { ignore_backslash_newline++; while ((c = getsc()) != '\0' && c != '\n') ; ignore_backslash_newline--; } ungetsc(c); } if (source->flags & SF_ALIAS) { /* trailing ' ' in alias definition */ source->flags &= ~SF_ALIAS; /* In POSIX mode, a trailing space only counts if we are * parsing a simple command */ if (!Flag(FPOSIX) || (cf & CMDWORD)) cf |= ALIAS; } /* Initial state: one of SBASE SHEREDELIM SWORD SASPAREN */ statep->ls_state = state; /* collect non-special or quoted characters to form word */ while (!((c = getsc()) == 0 || ((state == SBASE || state == SHEREDELIM) && ctype(c, C_LEX1)))) { Xcheck(ws, wp); switch (state) { case SBASE: if (c == '[' && (cf & (VARASN|ARRAYVAR))) { *wp = EOS; /* temporary */ if (is_wdvarname(Xstring(ws, wp), FALSE)) { char *p, *tmp; if (arraysub(&tmp)) { *wp++ = CHAR; *wp++ = c; for (p = tmp; *p; ) { Xcheck(ws, wp); *wp++ = CHAR; *wp++ = *p++; } afree(tmp, ATEMP); break; } else { Source *s; s = pushs(SREREAD, source->areap); s->start = s->str = s->u.freeme = tmp; s->next = source; source = s; } } *wp++ = CHAR; *wp++ = c; break; } /* fall through.. */ Sbase1: /* includes *(...|...) pattern (*+?@!) */#ifdef KSH if (c == '*' || c == '@' || c == '+' || c == '?' || c == '!') { c2 = getsc(); if (c2 == '(' /*)*/ ) { *wp++ = OPAT; *wp++ = c; PUSH_STATE(SPATTERN); break; } ungetsc(c2); }#endif /* KSH */ /* fall through.. */ Sbase2: /* doesn't include *(...|...) pattern (*+?@!) */ switch (c) { case '\\': c = getsc();#ifdef OS2 if (isalnum(c)) { *wp++ = CHAR, *wp++ = '\\'; *wp++ = CHAR, *wp++ = c; } else #endif if (c) /* trailing \ is lost */ *wp++ = QCHAR, *wp++ = c; break; case '\'': *wp++ = OQUOTE; ignore_backslash_newline++; PUSH_STATE(SSQUOTE); break; case '"': *wp++ = OQUOTE; PUSH_STATE(SDQUOTE); break; default: goto Subst; } break; Subst: switch (c) { case '\\': c = getsc(); switch (c) { case '"': case '\\': case '$': case '`': *wp++ = QCHAR, *wp++ = c; break; default: Xcheck(ws, wp); if (c) { /* trailing \ is lost */ *wp++ = CHAR, *wp++ = '\\'; *wp++ = CHAR, *wp++ = c; } break; } break; case '$': c = getsc(); if (c == '(') /*)*/ { c = getsc(); if (c == '(') /*)*/ { PUSH_STATE(SASPAREN); statep->ls_sasparen.nparen = 2; statep->ls_sasparen.start = Xsavepos(ws, wp); *wp++ = EXPRSUB; } else { ungetsc(c); PUSH_STATE(SCSPAREN); statep->ls_scsparen.nparen = 1; statep->ls_scsparen.csstate = 0; *wp++ = COMSUB; } } else if (c == '{') /*}*/ { *wp++ = OSUBST; *wp++ = '{'; /*}*/ wp = get_brace_var(&ws, wp); c = getsc(); /* allow :# and :% (ksh88 compat) */ if (c == ':') { *wp++ = CHAR, *wp++ = c; c = getsc(); } /* If this is a trim operation, * treat (,|,) specially in STBRACE. */ if (c == '#' || c == '%') { ungetsc(c); PUSH_STATE(STBRACE); } else { ungetsc(c); PUSH_STATE(SBRACE); } } else if (ctype(c, C_ALPHA)) { *wp++ = OSUBST; *wp++ = 'X'; do { Xcheck(ws, wp); *wp++ = c; c = getsc(); } while (ctype(c, C_ALPHA|C_DIGIT)); *wp++ = '\0'; *wp++ = CSUBST; *wp++ = 'X'; ungetsc(c); } else if (ctype(c, C_DIGIT|C_VAR1)) { Xcheck(ws, wp); *wp++ = OSUBST; *wp++ = 'X'; *wp++ = c; *wp++ = '\0'; *wp++ = CSUBST; *wp++ = 'X'; } else { *wp++ = CHAR, *wp++ = '$'; ungetsc(c); } break; case '`': PUSH_STATE(SBQUOTE); *wp++ = COMSUB; /* Need to know if we are inside double quotes * since sh/at&t-ksh translate the \" to " in * "`..\"..`". * This is not done in posix mode (section * 3.2.3, Double Quotes: "The backquote shall * retain its special meaning introducing the * other form of command substitution (see * 3.6.3). The portion of the quoted string * from the initial backquote and the * characters up to the next backquote that * is not preceded by a backslash (having * escape characters removed) defines that * command whose output replaces `...` when * the word is expanded." * Section 3.6.3, Command Substitution: * "Within the backquoted style of command * substitution, backslash shall retain its * literal meaning, except when followed by * $ ` \."). */ statep->ls_sbquote.indquotes = 0; if (!Flag(FPOSIX)) { Lex_state *s = statep; Lex_state *base = state_info.base; while (1) { for (; s != base; s--) { if (s->ls_state == SDQUOTE) { statep->ls_sbquote.indquotes = 1; break; } } if (s != base) break; if (!(s = s->ls_info.base)) break; base = s-- - STATE_BSIZE; } } break; default: *wp++ = CHAR, *wp++ = c; } break; case SSQUOTE: if (c == '\'') { POP_STATE(); *wp++ = CQUOTE; ignore_backslash_newline--; } else *wp++ = QCHAR, *wp++ = c; break; case SDQUOTE: if (c == '"') { POP_STATE(); *wp++ = CQUOTE; } else goto Subst; break; case SCSPAREN: /* $( .. ) */ /* todo: deal with $(...) quoting properly * kludge to partly fake quoting inside $(..): doesn't * really work because nested $(..) or ${..} inside * double quotes aren't dealt with. */ switch (statep->ls_scsparen.csstate) { case 0: /* normal */ switch (c) { case '(': statep->ls_scsparen.nparen++; break; case ')': statep->ls_scsparen.nparen--; break; case '\\': statep->ls_scsparen.csstate = 1; break; case '"': statep->ls_scsparen.csstate = 2; break; case '\'': statep->ls_scsparen.csstate = 4; ignore_backslash_newline++; break; } break; case 1: /* backslash in normal mode */ case 3: /* backslash in double quotes */ --statep->ls_scsparen.csstate; break; case 2: /* double quotes */ if (c == '"') statep->ls_scsparen.csstate = 0; else if (c == '\\') statep->ls_scsparen.csstate = 3; break; case 4: /* single quotes */ if (c == '\'') { statep->ls_scsparen.csstate = 0; ignore_backslash_newline--; } break; } if (statep->ls_scsparen.nparen == 0) { POP_STATE(); *wp++ = 0; /* end of COMSUB */ } else *wp++ = c; break; case SASPAREN: /* $(( .. )) */ /* todo: deal with $((...); (...)) properly */ /* XXX should nest using existing state machine * (embed "..", $(...), etc.) */ if (c == '(') statep->ls_sasparen.nparen++; else if (c == ')') { statep->ls_sasparen.nparen--; if (statep->ls_sasparen.nparen == 1) { /*(*/ if ((c2 = getsc()) == ')') { POP_STATE(); *wp++ = 0; /* end of EXPRSUB */ break; } else { char *s; ungetsc(c2); /* mismatched parenthesis - * assume we were really * parsing a $(..) expression */ s = Xrestpos(ws, wp, statep->ls_sasparen.start); memmove(s + 1, s, wp - s); *s++ = COMSUB; *s = '('; /*)*/ wp++; statep->ls_scsparen.nparen = 1; statep->ls_scsparen.csstate = 0; state = statep->ls_state = SCSPAREN; } } } *wp++ = c; break; case SBRACE: /*{*/ if (c == '}') { POP_STATE(); *wp++ = CSUBST; *wp++ = /*{*/ '}'; } else goto Sbase1; break; case STBRACE: /* Same as SBRACE, except (,|,) treated specially */ /*{*/ if (c == '}') { POP_STATE(); *wp++ = CSUBST; *wp++ = /*{*/ '}';Lines 1–500 of 1402. 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/* * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ /* * lexical analysis and source input */ #include "sh.h" #include <ctype.h> /* Structure to keep track of the lexing state and the various pieces of info * needed for each particular state. */ typedef struct lex_state Lex_state; struct lex_state { int ls_state; union { /* $(...) */ struct scsparen_info { int nparen; /* count open parenthesis */ int csstate; /* XXX remove */ #define ls_scsparen ls_info.u_scsparen } u_scsparen; /* $((...)) */ struct sasparen_info { int nparen; /* count open parenthesis */ int start; /* marks start of $(( in output str */ #define ls_sasparen ls_info.u_sasparen } u_sasparen; /* ((...)) */ struct sletparen_info { int nparen; /* count open parenthesis */ #define ls_sletparen ls_info.u_sletparen } u_sletparen; /* `...` */ struct sbquote_info { int indquotes; /* true if in double quotes: "`...`" */ #define ls_sbquote ls_info.u_sbquote } u_sbquote; Lex_state *base; /* used to point to next state block */ } ls_info; }; typedef struct State_info State_info; struct State_info { Lex_state *base; Lex_state *end; }; static void readhere ARGS((struct ioword *iop)); static int getsc__ ARGS((void)); static void getsc_line ARGS((Source *s)); static int getsc_bn ARGS((void)); static char *get_brace_var ARGS((XString *wsp, char *wp)); static int arraysub ARGS((char **strp)); static const char *ungetsc ARGS((int c)); static void gethere ARGS((void)); static Lex_state *push_state_ ARGS((State_info *si, Lex_state *old_end)); static Lex_state *pop_state_ ARGS((State_info *si, Lex_state *old_end)); static int backslash_skip; static int ignore_backslash_newline; /* optimized getsc_bn() */ #define getsc() (*source->str != '\0' && *source->str != '\\' \ && !backslash_skip ? *source->str++ : getsc_bn()) /* optimized getsc__() */ #define getsc_() ((*source->str != '\0') ? *source->str++ : getsc__()) #define STATE_BSIZE 32 #define PUSH_STATE(s) do { \ if (++statep == state_info.end) \ statep = push_state_(&state_info, statep); \ state = statep->ls_state = (s); \ } while (0) #define POP_STATE() do { \ if (--statep == state_info.base) \ statep = pop_state_(&state_info, statep); \ state = statep->ls_state; \ } while (0) /* * Lexical analyzer * * tokens are not regular expressions, they are LL(1). * for example, "${var:-${PWD}}", and "$(size $(whence ksh))". * hence the state stack. */ int yylex(cf) int cf; { Lex_state states[STATE_BSIZE], *statep; State_info state_info; register int c, state; XString ws; /* expandable output word */ register char *wp; /* output word pointer */ char *sp, *dp; int c2; Again: states[0].ls_state = -1; states[0].ls_info.base = (Lex_state *) 0; statep = &states[1]; state_info.base = states; state_info.end = &states[STATE_BSIZE]; Xinit(ws, wp, 64, ATEMP); backslash_skip = 0; ignore_backslash_newline = 0; if (cf&ONEWORD) state = SWORD; #ifdef KSH else if (cf&LETEXPR) { *wp++ = OQUOTE; /* enclose arguments in (double) quotes */ state = SLETPAREN; statep->ls_sletparen.nparen = 0; } #endif /* KSH */ else { /* normal lexing */ state = (cf & HEREDELIM) ? SHEREDELIM : SBASE; while ((c = getsc()) == ' ' || c == '\t') ; if (c == '#') { ignore_backslash_newline++; while ((c = getsc()) != '\0' && c != '\n') ; ignore_backslash_newline--; } ungetsc(c); } if (source->flags & SF_ALIAS) { /* trailing ' ' in alias definition */ source->flags &= ~SF_ALIAS; /* In POSIX mode, a trailing space only counts if we are * parsing a simple command */ if (!Flag(FPOSIX) || (cf & CMDWORD)) cf |= ALIAS; } /* Initial state: one of SBASE SHEREDELIM SWORD SASPAREN */ statep->ls_state = state; /* collect non-special or quoted characters to form word */ while (!((c = getsc()) == 0 || ((state == SBASE || state == SHEREDELIM) && ctype(c, C_LEX1)))) { Xcheck(ws, wp); switch (state) { case SBASE: if (c == '[' && (cf & (VARASN|ARRAYVAR))) { *wp = EOS; /* temporary */ if (is_wdvarname(Xstring(ws, wp), FALSE)) { char *p, *tmp; if (arraysub(&tmp)) { *wp++ = CHAR; *wp++ = c; for (p = tmp; *p; ) { Xcheck(ws, wp); *wp++ = CHAR; *wp++ = *p++; } afree(tmp, ATEMP); break; } else { Source *s; s = pushs(SREREAD, source->areap); s->start = s->str = s->u.freeme = tmp; s->next = source; source = s; } } *wp++ = CHAR; *wp++ = c; break; } /* fall through.. */ Sbase1: /* includes *(...|...) pattern (*+?@!) */ #ifdef KSH if (c == '*' || c == '@' || c == '+' || c == '?' || c == '!') { c2 = getsc(); if (c2 == '(' /*)*/ ) { *wp++ = OPAT; *wp++ = c; PUSH_STATE(SPATTERN); break; } ungetsc(c2); } #endif /* KSH */ /* fall through.. */ Sbase2: /* doesn't include *(...|...) pattern (*+?@!) */ switch (c) { case '\\': c = getsc(); #ifdef OS2 if (isalnum(c)) { *wp++ = CHAR, *wp++ = '\\'; *wp++ = CHAR, *wp++ = c; } else #endif if (c) /* trailing \ is lost */ *wp++ = QCHAR, *wp++ = c; break; case '\'': *wp++ = OQUOTE; ignore_backslash_newline++; PUSH_STATE(SSQUOTE); break; case '"': *wp++ = OQUOTE; PUSH_STATE(SDQUOTE); break; default: goto Subst; } break; Subst: switch (c) { case '\\': c = getsc(); switch (c) { case '"': case '\\': case '$': case '`': *wp++ = QCHAR, *wp++ = c; break; default: Xcheck(ws, wp); if (c) { /* trailing \ is lost */ *wp++ = CHAR, *wp++ = '\\'; *wp++ = CHAR, *wp++ = c; } break; } break; case '$': c = getsc(); if (c == '(') /*)*/ { c = getsc(); if (c == '(') /*)*/ { PUSH_STATE(SASPAREN); statep->ls_sasparen.nparen = 2; statep->ls_sasparen.start = Xsavepos(ws, wp); *wp++ = EXPRSUB; } else { ungetsc(c); PUSH_STATE(SCSPAREN); statep->ls_scsparen.nparen = 1; statep->ls_scsparen.csstate = 0; *wp++ = COMSUB; } } else if (c == '{') /*}*/ { *wp++ = OSUBST; *wp++ = '{'; /*}*/ wp = get_brace_var(&ws, wp); c = getsc(); /* allow :# and :% (ksh88 compat) */ if (c == ':') { *wp++ = CHAR, *wp++ = c; c = getsc(); } /* If this is a trim operation, * treat (,|,) specially in STBRACE. */ if (c == '#' || c == '%') { ungetsc(c); PUSH_STATE(STBRACE); } else { ungetsc(c); PUSH_STATE(SBRACE); } } else if (ctype(c, C_ALPHA)) { *wp++ = OSUBST; *wp++ = 'X'; do { Xcheck(ws, wp); *wp++ = c; c = getsc(); } while (ctype(c, C_ALPHA|C_DIGIT)); *wp++ = '\0'; *wp++ = CSUBST; *wp++ = 'X'; ungetsc(c); } else if (ctype(c, C_DIGIT|C_VAR1)) { Xcheck(ws, wp); *wp++ = OSUBST; *wp++ = 'X'; *wp++ = c; *wp++ = '\0'; *wp++ = CSUBST; *wp++ = 'X'; } else { *wp++ = CHAR, *wp++ = '$'; ungetsc(c); } break; case '`': PUSH_STATE(SBQUOTE); *wp++ = COMSUB; /* Need to know if we are inside double quotes * since sh/at&t-ksh translate the \" to " in * "`..\"..`". * This is not done in posix mode (section * 3.2.3, Double Quotes: "The backquote shall * retain its special meaning introducing the * other form of command substitution (see * 3.6.3). The portion of the quoted string * from the initial backquote and the * characters up to the next backquote that * is not preceded by a backslash (having * escape characters removed) defines that * command whose output replaces `...` when * the word is expanded." * Section 3.6.3, Command Substitution: * "Within the backquoted style of command * substitution, backslash shall retain its * literal meaning, except when followed by * $ ` \."). */ statep->ls_sbquote.indquotes = 0; if (!Flag(FPOSIX)) { Lex_state *s = statep; Lex_state *base = state_info.base; while (1) { for (; s != base; s--) { if (s->ls_state == SDQUOTE) { statep->ls_sbquote.indquotes = 1; break; } } if (s != base) break; if (!(s = s->ls_info.base)) break; base = s-- - STATE_BSIZE; } } break; default: *wp++ = CHAR, *wp++ = c; } break; case SSQUOTE: if (c == '\'') { POP_STATE(); *wp++ = CQUOTE; ignore_backslash_newline--; } else *wp++ = QCHAR, *wp++ = c; break; case SDQUOTE: if (c == '"') { POP_STATE(); *wp++ = CQUOTE; } else goto Subst; break; case SCSPAREN: /* $( .. ) */ /* todo: deal with $(...) quoting properly * kludge to partly fake quoting inside $(..): doesn't * really work because nested $(..) or ${..} inside * double quotes aren't dealt with. */ switch (statep->ls_scsparen.csstate) { case 0: /* normal */ switch (c) { case '(': statep->ls_scsparen.nparen++; break; case ')': statep->ls_scsparen.nparen--; break; case '\\': statep->ls_scsparen.csstate = 1; break; case '"': statep->ls_scsparen.csstate = 2; break; case '\'': statep->ls_scsparen.csstate = 4; ignore_backslash_newline++; break; } break; case 1: /* backslash in normal mode */ case 3: /* backslash in double quotes */ --statep->ls_scsparen.csstate; break; case 2: /* double quotes */ if (c == '"') statep->ls_scsparen.csstate = 0; else if (c == '\\') statep->ls_scsparen.csstate = 3; break; case 4: /* single quotes */ if (c == '\'') { statep->ls_scsparen.csstate = 0; ignore_backslash_newline--; } break; } if (statep->ls_scsparen.nparen == 0) { POP_STATE(); *wp++ = 0; /* end of COMSUB */ } else *wp++ = c; break; case SASPAREN: /* $(( .. )) */ /* todo: deal with $((...); (...)) properly */ /* XXX should nest using existing state machine * (embed "..", $(...), etc.) */ if (c == '(') statep->ls_sasparen.nparen++; else if (c == ')') { statep->ls_sasparen.nparen--; if (statep->ls_sasparen.nparen == 1) { /*(*/ if ((c2 = getsc()) == ')') { POP_STATE(); *wp++ = 0; /* end of EXPRSUB */ break; } else { char *s; ungetsc(c2); /* mismatched parenthesis - * assume we were really * parsing a $(..) expression */ s = Xrestpos(ws, wp, statep->ls_sasparen.start); memmove(s + 1, s, wp - s); *s++ = COMSUB; *s = '('; /*)*/ wp++; statep->ls_scsparen.nparen = 1; statep->ls_scsparen.csstate = 0; state = statep->ls_state = SCSPAREN; } } } *wp++ = c; break; case SBRACE: /*{*/ if (c == '}') { POP_STATE(); *wp++ = CSUBST; *wp++ = /*{*/ '}'; } else goto Sbase1; break; case STBRACE: /* Same as SBRACE, except (,|,) treated specially */ /*{*/ if (c == '}') { POP_STATE(); *wp++ = CSUBST; *wp++ = /*{*/ '}';