From f07a4c844da9f0ecae5bbee1ab94be56505f26f7 Mon Sep 17 00:00:00 2001 From: Thomas Bushnell Date: Tue, 25 Feb 1997 21:28:37 +0000 Subject: Initial source --- ddb/db_lex.c | 455 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 455 insertions(+) create mode 100644 ddb/db_lex.c (limited to 'ddb/db_lex.c') diff --git a/ddb/db_lex.c b/ddb/db_lex.c new file mode 100644 index 0000000..617f123 --- /dev/null +++ b/ddb/db_lex.c @@ -0,0 +1,455 @@ +/* + * Mach Operating System + * Copyright (c) 1991,1990 Carnegie Mellon University + * All Rights Reserved. + * + * Permission to use, copy, modify and distribute this software and its + * documentation is hereby granted, provided that both the copyright + * notice and this permission notice appear in all copies of the + * software, derivative works or modified versions, and any portions + * thereof, and that both notices appear in supporting documentation. + * + * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" + * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR + * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * Carnegie Mellon requests users of this software to return to + * + * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU + * School of Computer Science + * Carnegie Mellon University + * Pittsburgh PA 15213-3890 + * + * any improvements or extensions that they make and grant Carnegie Mellon + * the rights to redistribute these changes. + */ +/* + * Author: David B. Golub, Carnegie Mellon University + * Date: 7/90 + */ +#include "mach_kdb.h" +#if MACH_KDB + +/* + * Lexical analyzer. + */ +#include +#include +#include + +char db_line[DB_LEX_LINE_SIZE]; +char db_last_line[DB_LEX_LINE_SIZE]; +char *db_lp, *db_endlp; +char *db_last_lp; +int db_look_char = 0; +db_expr_t db_look_token = 0; + +int +db_read_line(repeat_last) + char *repeat_last; +{ + int i; + + i = db_readline(db_line, sizeof(db_line)); + if (i == 0) + return (0); /* EOI */ + if (repeat_last) { + if (strncmp(db_line, repeat_last, strlen(repeat_last)) == 0) { + db_strcpy(db_line, db_last_line); + db_printf("%s", db_line); + i = strlen(db_line); + } else if (db_line[0] != '\n' && db_line[0] != 0) + db_strcpy(db_last_line, db_line); + } + db_lp = db_line; + db_endlp = db_lp + i; + db_last_lp = db_lp; + db_look_char = 0; + db_look_token = 0; + return (i); +} + +void +db_flush_line() +{ + db_lp = db_line; + db_last_lp = db_lp; + db_endlp = db_line; +} + +void +db_switch_input(buffer, size) + char *buffer; + int size; +{ + db_lp = buffer; + db_last_lp = db_lp; + db_endlp = buffer + size; + db_look_char = 0; + db_look_token = 0; +} + +void +db_save_lex_context(lp) + register struct db_lex_context *lp; +{ + lp->l_ptr = db_lp; + lp->l_eptr = db_endlp; + lp->l_char = db_look_char; + lp->l_token = db_look_token; +} + +void +db_restore_lex_context(lp) + register struct db_lex_context *lp; +{ + db_lp = lp->l_ptr; + db_last_lp = db_lp; + db_endlp = lp->l_eptr; + db_look_char = lp->l_char; + db_look_token = lp->l_token; +} + +int +db_read_char() +{ + int c; + + if (db_look_char != 0) { + c = db_look_char; + db_look_char = 0; + } + else if (db_lp >= db_endlp) + c = -1; + else + c = *db_lp++; + return (c); +} + +void +db_unread_char(c) + int c; +{ + db_look_char = c; +} + +void +db_unread_token(t) + int t; +{ + db_look_token = t; +} + +int +db_read_token() +{ + int t; + + if (db_look_token) { + t = db_look_token; + db_look_token = 0; + } + else { + db_last_lp = db_lp; + if (db_look_char) + db_last_lp--; + t = db_lex(); + } + return (t); +} + +db_expr_t db_tok_number; +char db_tok_string[TOK_STRING_SIZE]; +db_expr_t db_radix = 16; + +void +db_flush_lex() +{ + db_flush_line(); + db_look_char = 0; + db_look_token = 0; +} + +#define DB_DISP_SKIP 40 /* number of chars to display skip */ + +void +db_skip_to_eol() +{ + register skip; + register t; + register n; + register char *p; + + t = db_read_token(); + p = db_last_lp; + for (skip = 0; t != tEOL && t != tSEMI_COLON && t != tEOF; skip++) + t = db_read_token(); + if (t == tSEMI_COLON) + db_unread_token(t); + if (skip != 0) { + while (p < db_last_lp && (*p == ' ' || *p == '\t')) + p++; + db_printf("Warning: Skipped input data \""); + for (n = 0; n < DB_DISP_SKIP && p < db_last_lp; n++) + db_printf("%c", *p++); + if (n >= DB_DISP_SKIP) + db_printf("...."); + db_printf("\"\n"); + } +} + +int +db_lex() +{ + register char *cp; + register c; + + c = db_read_char(); + while (c <= ' ' || c > '~') { + if (c == '\n' || c == -1) + return (tEOL); + c = db_read_char(); + } + + cp = db_tok_string; + *cp++ = c; + + if (c >= '0' && c <= '9') { + /* number */ + int r, digit; + + if (c > '0') + r = db_radix; + else { + c = db_read_char(); + if (c == 'O' || c == 'o') + r = 8; + else if (c == 'T' || c == 't') + r = 10; + else if (c == 'X' || c == 'x') + r = 16; + else { + cp--; + r = db_radix; + db_unread_char(c); + } + c = db_read_char(); + *cp++ = c; + } + db_tok_number = 0; + for (;;) { + if (c >= '0' && c <= ((r == 8) ? '7' : '9')) + digit = c - '0'; + else if (r == 16 && ((c >= 'A' && c <= 'F') || + (c >= 'a' && c <= 'f'))) { + if (c >= 'a') + digit = c - 'a' + 10; + else + digit = c - 'A' + 10; + } + else + break; + db_tok_number = db_tok_number * r + digit; + c = db_read_char(); + if (cp < &db_tok_string[sizeof(db_tok_string)-1]) + *cp++ = c; + } + cp[-1] = 0; + if ((c >= '0' && c <= '9') || + (c >= 'A' && c <= 'Z') || + (c >= 'a' && c <= 'z') || + (c == '_')) + { + db_printf("Bad character '%c' after number %s\n", + c, db_tok_string); + db_error(0); + db_flush_lex(); + return (tEOF); + } + db_unread_char(c); + return (tNUMBER); + } + if ((c >= 'A' && c <= 'Z') || + (c >= 'a' && c <= 'z') || + c == '_' || c == '\\' || c == ':') + { + /* identifier */ + if (c == '\\') { + c = db_read_char(); + if (c == '\n' || c == -1) + db_error("Bad '\\' at the end of line\n"); + cp[-1] = c; + } + while (1) { + c = db_read_char(); + if ((c >= 'A' && c <= 'Z') || + (c >= 'a' && c <= 'z') || + (c >= '0' && c <= '9') || + c == '_' || c == '\\' || c == ':' || c == '.') + { + if (c == '\\') { + c = db_read_char(); + if (c == '\n' || c == -1) + db_error("Bad '\\' at the end of line\n"); + } + *cp++ = c; + if (cp == db_tok_string+sizeof(db_tok_string)) { + db_error("String too long\n"); + db_flush_lex(); + return (tEOF); + } + continue; + } + else { + *cp = '\0'; + break; + } + } + db_unread_char(c); + return (tIDENT); + } + + *cp = 0; + switch (c) { + case '+': + return (tPLUS); + case '-': + return (tMINUS); + case '.': + c = db_read_char(); + if (c == '.') { + *cp++ = c; + *cp = 0; + return (tDOTDOT); + } + db_unread_char(c); + return (tDOT); + case '*': + return (tSTAR); + case '/': + return (tSLASH); + case '=': + c = db_read_char(); + if (c == '=') { + *cp++ = c; + *cp = 0; + return(tLOG_EQ); + } + db_unread_char(c); + return (tEQ); + case '%': + return (tPCT); + case '#': + return (tHASH); + case '(': + return (tLPAREN); + case ')': + return (tRPAREN); + case ',': + return (tCOMMA); + case '\'': + return (tQUOTE); + case '"': + /* string */ + cp = db_tok_string; + c = db_read_char(); + while (c != '"' && c > 0 && c != '\n') { + if (cp >= &db_tok_string[sizeof(db_tok_string)-1]) { + db_error("Too long string\n"); + db_flush_lex(); + return (tEOF); + } + if (c == '\\') { + c = db_read_char(); + switch(c) { + case 'n': + c = '\n'; break; + case 't': + c = '\t'; break; + case '\\': + case '"': + break; + default: + db_printf("Bad escape sequence '\\%c'\n", c); + db_error(0); + db_flush_lex(); + return (tEOF); + } + } + *cp++ = c; + c = db_read_char(); + } + *cp = 0; + if (c != '"') { + db_error("Non terminated string constant\n"); + db_flush_lex(); + return (tEOF); + } + return (tSTRING); + case '$': + return (tDOLLAR); + case '!': + c = db_read_char(); + if (c == '=') { + *cp++ = c; + *cp = 0; + return(tLOG_NOT_EQ); + } + db_unread_char(c); + return (tEXCL); + case '&': + c = db_read_char(); + if (c == '&') { + *cp++ = c; + *cp = 0; + return(tLOG_AND); + } + db_unread_char(c); + return(tBIT_AND); + case '|': + c = db_read_char(); + if (c == '|') { + *cp++ = c; + *cp = 0; + return(tLOG_OR); + } + db_unread_char(c); + return(tBIT_OR); + case '<': + c = db_read_char(); + *cp++ = c; + *cp = 0; + if (c == '<') + return (tSHIFT_L); + if (c == '=') + return (tLESS_EQ); + cp[-1] = 0; + db_unread_char(c); + return(tLESS); + break; + case '>': + c = db_read_char(); + *cp++ = c; + *cp = 0; + if (c == '>') + return (tSHIFT_R); + if (c == '=') + return (tGREATER_EQ); + cp[-1] = 0; + db_unread_char(c); + return (tGREATER); + break; + case ';': + return (tSEMI_COLON); + case '?': + return (tQUESTION); + case -1: + db_strcpy(db_tok_string, ""); + return (tEOF); + } + db_printf("Bad character '%c'\n", c); + db_flush_lex(); + return (tEOF); +} + +#endif MACH_KDB -- cgit v1.2.3