% This file is part of CWEB.% This program by Silvio Levy and Donald E. Knuth% is based on a program by Knuth.% It is distributed WITHOUT ANY WARRANTY, express or implied.% Version 4.3 --- May 2021 (works also with later versions) % Copyright (C) 1987,1990,1993 Silvio Levy and Donald E. Knuth % Permission is granted to make and distribute verbatim copies of this% document provided that the copyright notice and this permission notice% are preserved on all copies. % Permission is granted to copy and distribute modified versions of this% document under the conditions for verbatim copying, provided that the% entire resulting derived work is distributed under the terms of a% permission notice identical to this one. % Amendments to 'common.h' resulting in this updated version were created% by numerous collaborators over the course of many years. % Please send comments, suggestions, etc. to tex-k@@tug.org. % The next few sections contain stuff from the file |"common.w"| that has% to be included in both |"ctangle.w"| and |"cweave.w"|. It appears in this% file |"common.h"|, which is also included in |"common.w"| to propagate% possible changes from this single source consistently. First comes general stuff: @i iso_types.w @d ctangle false@d cweave true @<Common code...@>=typedef bool boolean;typedef uint8_t eight_bits;typedef uint16_t sixteen_bits;extern boolean program; /* \.{CWEAVE} or \.{CTANGLE}? */extern int phase; /* which phase are we in? */ @ Interface to the standard \CEE/ library: @<Include files@>=#include <ctype.h> /* definition of |@!isalpha|, |@!isdigit| and so on */#include <stdbool.h> /* definition of |@!bool|, |@!true| and |@!false| */#include <stddef.h> /* definition of |@!ptrdiff_t| */#include <stdint.h> /* definition of |@!uint8_t| and |@!uint16_t| */#include <stdlib.h> /* definition of |@!getenv| and |@!exit| */#include <stdio.h> /* definition of |@!printf| and friends */#include <string.h> /* definition of |@!strlen|, |@!strcmp| and so on */ @ Code related to the character set:@^ASCII code dependencies@> @d and_and 04 /* `\.{\&\&}'\,; corresponds to MIT's {\tentex\char'4} */@d lt_lt 020 /* `\.{<<}'\,; corresponds to MIT's {\tentex\char'20} */@d gt_gt 021 /* `\.{>>}'\,; corresponds to MIT's {\tentex\char'21} */@d plus_plus 013 /* `\.{++}'\,; corresponds to MIT's {\tentex\char'13} */@d minus_minus 01 /* `\.{--}'\,; corresponds to MIT's {\tentex\char'1} */@d minus_gt 031 /* `\.{->}'\,; corresponds to MIT's {\tentex\char'31} */@d non_eq 032 /* `\.{!=}'\,; corresponds to MIT's {\tentex\char'32} */@d lt_eq 034 /* `\.{<=}'\,; corresponds to MIT's {\tentex\char'34} */@d gt_eq 035 /* `\.{>=}'\,; corresponds to MIT's {\tentex\char'35} */@d eq_eq 036 /* `\.{==}'\,; corresponds to MIT's {\tentex\char'36} */@d or_or 037 /* `\.{\v\v}'\,; corresponds to MIT's {\tentex\char'37} */@d dot_dot_dot 016 /* `\.{...}'\,; corresponds to MIT's {\tentex\char'16} */@d colon_colon 06 /* `\.{::}'\,; corresponds to MIT's {\tentex\char'6} */@d period_ast 026 /* `\.{.*}'\,; corresponds to MIT's {\tentex\char'26} */@d minus_gt_ast 027 /* `\.{->*}'\,; corresponds to MIT's {\tentex\char'27} */@#@d compress(c) if (loc++<=limit) return c @<Common code...@>=extern char section_text[]; /* text being sought for */extern char *section_text_end; /* end of |section_text| */extern char *id_first; /* where the current identifier begins in the buffer */extern char *id_loc; /* just after the current identifier in the buffer */ @ Code related to input routines:@d xisalpha(c) (isalpha((eight_bits)(c))&&((eight_bits)(c)<0200))@d xisdigit(c) (isdigit((eight_bits)(c))&&((eight_bits)(c)<0200))@d xisspace(c) (isspace((eight_bits)(c))&&((eight_bits)(c)<0200))@d xislower(c) (islower((eight_bits)(c))&&((eight_bits)(c)<0200))@d xisupper(c) (isupper((eight_bits)(c))&&((eight_bits)(c)<0200))@d xisxdigit(c) (isxdigit((eight_bits)(c))&&((eight_bits)(c)<0200))@d isxalpha(c) ((c)=='_' || (c)=='$')  /* non-alpha characters allowed in identifier */@d ishigh(c) ((eight_bits)(c)>0177)@^high-bit character handling@> @<Common code...@>=extern char buffer[]; /* where each line of input goes */extern char *buffer_end; /* end of |buffer| */extern char *loc; /* points to the next character to be read from the buffer */extern char *limit; /* points to the last character in the buffer */ @ Code related to file handling:@f line x /* make |line| an unreserved word */@d max_include_depth 10 /* maximum number of source files open  simultaneously, not counting the change file */@d max_file_name_length 1024@d cur_file file[include_depth] /* current file */@d cur_file_name file_name[include_depth] /* current file name */@d cur_line line[include_depth] /* number of current line in current file */@d web_file file[0] /* main source file */@d web_file_name file_name[0] /* main source file name */ @<Common code...@>=extern int include_depth; /* current level of nesting */extern FILE *file[]; /* stack of non-change files */extern FILE *change_file; /* change file */extern char file_name[][max_file_name_length];  /* stack of non-change file names */extern char change_file_name[]; /* name of change file */extern int line[]; /* number of current line in the stacked files */extern int change_line; /* number of current line in change file */extern int change_depth; /* where \.{@@y} originated during a change */extern boolean input_has_ended; /* if there is no more input */extern boolean changing; /* if the current line is from |change_file| */extern boolean web_file_open; /* if the web file is being read */ @ @<Predecl...@>=extern boolean get_line(void); /* inputs the next line */extern void check_complete(void); /* checks that all changes were picked up */extern void reset_input(void); /* initialize to read the web file and change file */ @ Code related to section numbers:@<Common code...@>=extern sixteen_bits section_count; /* the current section number */extern boolean changed_section[]; /* is the section changed? */extern boolean change_pending; /* is a decision about change still unclear? */extern boolean print_where; /* tells \.{CTANGLE} to print line and file info */ @ Code related to identifier and section name storage:@d length(c) (size_t)((c+1)->byte_start-(c)->byte_start) /* the length of a name */@d print_id(c) term_write((c)->byte_start,length((c))) /* print identifier */@d llink link /* left link in binary search tree for section names */@d rlink dummy.Rlink /* right link in binary search tree for section names */@d root name_dir->rlink /* the root of the binary search tree  for section names */ @<Common code...@>=typedef struct name_info {  char *byte_start; /* beginning of the name in |byte_mem| */  struct name_info *link;  union {    struct name_info *Rlink; /* right link in binary search tree for section      names */    char Ilk; /* used by identifiers in \.{CWEAVE} only */  } dummy;  void *equiv_or_xref; /* info corresponding to names */} name_info; /* contains information about an identifier or section name */typedef name_info *name_pointer; /* pointer into array of \&{name\_info}s */typedef name_pointer *hash_pointer;extern char byte_mem[]; /* characters of names */extern char *byte_mem_end; /* end of |byte_mem| */extern char *byte_ptr; /* first unused position in |byte_mem| */extern name_info name_dir[]; /* information about names */extern name_pointer name_dir_end; /* end of |name_dir| */extern name_pointer name_ptr; /* first unused position in |name_dir| */extern name_pointer hash[]; /* heads of hash lists */extern hash_pointer hash_end; /* end of |hash| */extern hash_pointer h; /* index into hash-head array */ @ @<Predecl...@>=extern boolean names_match(name_pointer,const char *,size_t,eight_bits);@/extern name_pointer id_lookup(const char *,const char *,char);   /* looks up a string in the identifier table */extern name_pointer section_lookup(char *,char *,boolean); /* finds section name */extern void init_node(name_pointer);@/extern void init_p(name_pointer,eight_bits);@/extern void print_prefix_name(name_pointer);@/extern void print_section_name(name_pointer);@/extern void sprint_section_name(char *,name_pointer); @ Code related to error handling:@d spotless 0 /* |history| value for normal jobs */@d harmless_message 1 /* |history| value when non-serious info was printed */@d error_message 2 /* |history| value when an error was noted */@d fatal_message 3 /* |history| value when we had to stop prematurely */@d mark_harmless if (history==spotless) history=harmless_message@d mark_error history=error_message@d confusion(s) fatal("! This can't happen: ",s)@.This can't happen@> @<Common code...@>=extern int history; /* indicates how bad this run was */ @ @<Predecl...@>=extern int wrap_up(void); /* indicate |history| and exit */extern void err_print(const char *); /* print error message and context */extern void fatal(const char *,const char *); /* issue error message and die */extern void overflow(const char *); /* succumb because a table has overflowed */ @ Code related to command line arguments:@d show_banner flags['b'] /* should the banner line be printed? */@d show_progress flags['p'] /* should progress reports be printed? */@d show_happiness flags['h'] /* should lack of errors be announced? */@d show_stats flags['s'] /* should statistics be printed at end of run? */@d make_xrefs flags['x'] /* should cross references be output? */ @<Common code...@>=extern int argc; /* copy of |ac| parameter to |main| */extern char **argv; /* copy of |av| parameter to |main| */extern char C_file_name[]; /* name of |C_file| */extern char tex_file_name[]; /* name of |tex_file| */extern char idx_file_name[]; /* name of |idx_file| */extern char scn_file_name[]; /* name of |scn_file| */extern boolean flags[]; /* an option for each 7-bit code */ @ Code related to output:@d update_terminal fflush(stdout) /* empty the terminal output buffer */@d new_line putchar('\n')@d term_write(a,b) fflush(stdout),fwrite(a,sizeof(char),b,stdout) @<Common code...@>=extern FILE *C_file; /* where output of \.{CTANGLE} goes */extern FILE *tex_file; /* where output of \.{CWEAVE} goes */extern FILE *idx_file; /* where index from \.{CWEAVE} goes */extern FILE *scn_file; /* where list of sections from \.{CWEAVE} goes */extern FILE *active_file; /* currently active file for \.{CWEAVE} output */ @ The procedure that gets everything rolling:@<Predecl...@>=extern void common_init(void);@/extern void print_stats(void); @ The following parameters were sufficient in the original \.{WEB} tohandle \TEX/, so they should be sufficient for most applications of\.{CWEB}. @d max_bytes 1000000 /* the number of bytes in identifiers,  index entries, and section names */@d max_toks 1000000 /* number of bytes in compressed \CEE/ code */@d max_names 10239 /* number of identifiers, strings, section names;  must be less than 10240 */@d max_sections 4000 /* greater than the total number of sections */@d max_texts 10239 /* number of replacement texts, must be less than 10240 */@d longest_name 10000 /* file and section names and section texts shouldn't be longer than this */@d stack_size 500 /* number of simultaneous levels of macro expansion */@d buf_size 1000 /* maximum length of input line, plus one */@d long_buf_size (buf_size+longest_name) /* for \.{CWEAVE} */ @ End of \.{COMMON} interface.