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|
; returns a string of null character-separated preprocessing tokens and space characters
; this corresponds to translation phases 1-3 in the C89 standard
; each sequence of two or more spaces is replaced with a single space
; spaces around # and ## are removed
function split_into_preprocessing_tokens
argument filename
local fd
local file_contents
local pptokens
local pptokens2
local p
local b
local c
local in
local out
local n
local line_number
fd = open_r(filename)
file_contents = malloc(2000000)
pptokens = malloc(2000000)
p = file_contents
:pptokens_read_loop
n = syscall(0, fd, p, 4096)
if n == 0 goto pptokens_read_loop_end
p += n
goto pptokens_read_loop
:pptokens_read_loop_end
p -= 1
if *1p != 10 goto no_newline_at_end_of_file
; okay we read the file. first, delete every backslash-newline sequence (phase 2)
local newlines ; we add more newlines to keep line numbers right
newlines = 1
in = file_contents
out = file_contents
:backslashnewline_loop
c = *1in
if c == 0 goto backslashnewline_loop_end
if c == 10 goto proper_newline_loop
if c != '\ goto not_backslashnewline
p = in + 1
c = *1p
if c != 10 goto not_backslashnewline
in += 2 ; skip backlash and newline
newlines += 1 ; add one additional newline the next time around to compensate
goto backslashnewline_loop
:not_backslashnewline
*1out = *1in
out += 1
in += 1
goto backslashnewline_loop
:proper_newline_loop
if newlines == 0 goto proper_newline_loop_end
; output a newline
*1out = 10
out += 1
newlines -= 1
goto proper_newline_loop
:proper_newline_loop_end
newlines = 1
in += 1
goto backslashnewline_loop
:backslashnewline_loop_end
*1out = 0
; @NONSTANDARD: this is where trigraphs would go
; split file into preprocessing tokens, remove comments (phase 3)
; we're still doing the trick with newlines, this time for ones inside comments
; this is needed because the following is legal C:
; #include/*
; */<stdio.h>
; and is not equivalent to:
; #include
; <stdio.h>
newlines = 1
in = file_contents
out = pptokens
line_number = 1
:pptokens_loop
c = *1in
if c == 10 goto pptokens_newline_loop
if c == 0 goto pptokens_loop_end
if c == 32 goto pptoken_space
if c == 9 goto pptoken_space
b = isdigit(c)
if b != 0 goto pptoken_number
b = isalpha_or_underscore(c)
if b != 0 goto pptoken_identifier
b = str_startswith(in, .str_comment_start)
if b != 0 goto pptoken_comment
; now we check for all the various operators and symbols in C
if c == 59 goto pptoken_single_character ; semicolon
if c == '( goto pptoken_single_character
if c == ') goto pptoken_single_character
if c == '[ goto pptoken_single_character
if c == '] goto pptoken_single_character
if c == '{ goto pptoken_single_character
if c == '} goto pptoken_single_character
if c == ', goto pptoken_single_character
if c == '~ goto pptoken_single_character
if c == '? goto pptoken_single_character
if c == ': goto pptoken_single_character
if c == '" goto pptoken_string_or_char_literal
if c == '' goto pptoken_string_or_char_literal
b = str_startswith(in, .str_lshift_eq)
if b != 0 goto pptoken_3_chars
b = str_startswith(in, .str_rshift_eq)
if b != 0 goto pptoken_3_chars
b = str_startswith(in, .str_eq_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_not_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_gt_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_lt_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_plus_plus)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_minus_minus)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_plus_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_minus_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_times_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_div_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_remainder_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_and_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_or_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_xor_eq)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_and_and)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_or_or)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_lshift)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_rshift)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_arrow)
if b != 0 goto pptoken_2_chars
b = str_startswith(in, .str_dotdotdot)
if b != 0 goto pptoken_3_chars
b = str_startswith(in, .str_hash_hash)
if b != 0 goto pptoken_2_chars
if c == '+ goto pptoken_single_character
if c == '- goto pptoken_single_character
if c == '* goto pptoken_single_character
if c == '/ goto pptoken_single_character
if c == '% goto pptoken_single_character
if c == '& goto pptoken_single_character
if c == '| goto pptoken_single_character
if c == '^ goto pptoken_single_character
if c == '> goto pptoken_single_character
if c == '< goto pptoken_single_character
if c == '! goto pptoken_single_character
if c == '= goto pptoken_single_character
if c == '# goto pptoken_single_character
if c == '. goto pptoken_dot
goto bad_pptoken
:pptoken_comment
; emit a space ("Each comment is replaced by one space character.")
*1out = 32
out += 1
*1out = 0
out += 1
; skip over comment
:pptoken_comment_loop
b = str_startswith(in, .str_comment_end)
if b != 0 goto pptoken_comment_loop_end
c = *1in
in += 1
if c == 0 goto unterminated_comment
if c == 10 goto pptoken_comment_newline
goto pptoken_comment_loop
:pptoken_comment_loop_end
in += 2 ; skip */
goto pptokens_loop
:pptoken_comment_newline
; keep line numbers correct
newlines += 1
goto pptoken_comment_loop
:pptoken_dot
; could just be a . or could be .3 -- we need to check if *(in+1) is a digit
p = in + 1
b = isdigit(*1p)
if b != 0 goto pptoken_number
; okay it's just a dot
goto pptoken_single_character
:pptoken_string_or_char_literal
local delimiter
local backslash
delimiter = c
backslash = 0
*1out = c
out += 1
in += 1
:pptoken_strchar_loop
c = *1in
*1out = c
in += 1
out += 1
if c == '\ goto pptoken_strchar_backslash
if c == 10 goto unterminated_string
if c == 0 goto unterminated_string
b = backslash
backslash = 0
if b == 1 goto pptoken_strchar_loop ; string can't end with an odd number of backslashes
if c == delimiter goto pptoken_strchar_loop_end
goto pptoken_strchar_loop
:pptoken_strchar_backslash
backslash ^= 1
goto pptoken_strchar_loop
:pptoken_strchar_loop_end
*1out = 0
out += 1
goto pptokens_loop
:pptoken_number
c = *1in
b = is_ppnumber_char(c)
if b == 0 goto pptoken_number_end
*1out = c
out += 1
in += 1
if c == 'e goto pptoken_number_e
if c == 'E goto pptoken_number_e
goto pptoken_number
:pptoken_number_e
c = *1in
if c == '+ goto pptoken_number_sign
if c == '- goto pptoken_number_sign
goto pptoken_number
:pptoken_number_sign
; special code to handle + - immediately following e
*1out = c
in += 1
out += 1
goto pptoken_number
:pptoken_number_end
*1out = 0
out += 1
goto pptokens_loop
:pptoken_identifier
c = *1in
b = isalnum_or_underscore(c)
if b == 0 goto pptoken_identifier_end
*1out = c
in += 1
out += 1
goto pptoken_identifier
:pptoken_identifier_end
*1out = 0
out += 1
goto pptokens_loop
:pptoken_space
; space character token
*1out = 32
in += 1
out += 1
*1out = 0
out += 1
goto pptokens_loop
:pptoken_single_character
; a single character preprocessing token, like {?}
*1out = c
in += 1
out += 1
*1out = 0
out += 1
goto pptokens_loop
:pptoken_2_chars
; two-character pptoken (e.g. ##)
*1out = c
in += 1
out += 1
*1out = *1in
in += 1
out += 1
*1out = 0
out += 1
goto pptokens_loop
:pptoken_3_chars
; three-character pptoken (e.g. >>=)
*1out = c
in += 1
out += 1
*1out = *1in
in += 1
out += 1
*1out = *1in
in += 1
out += 1
*1out = 0
out += 1
goto pptokens_loop
:pptokens_newline_loop
if newlines == 0 goto pptokens_newline_loop_end
; output a newline
*1out = 10
out += 1
*1out = 0
out += 1
line_number += 1
newlines -= 1
goto pptokens_newline_loop
:pptokens_newline_loop_end
newlines = 1
in += 1
goto pptokens_loop
:pptokens_loop_end
pptokens2 = file_contents ; repurpose file contents
; replace each sequence of two or more spaces with a single space
; "Whether each nonempty sequence of other white-space characters is
; retained or replaced by one space character is implementation-defined." (C89 § 2.1.1.2)
in = pptokens
out = pptokens2
:join_spaces_loop
if *1in == 0 goto join_spaces_loop_end
c = *1in
pptoken_copy_and_advance(&in, &out)
if c == 32 goto join_spaces
goto join_spaces_loop
:join_spaces
pptoken_skip_spaces(&in)
goto join_spaces_loop
:join_spaces_loop_end
*1out = 0
; delete space surrounding ## and #
; we want to delete spaces before # so that all preprocessor directives are at the start of the line
; (this makes recognizing them slightly easier)
in = pptokens2
out = pptokens
:delete_hash_spaces_loop
c = *1in
if c == 0 goto delete_hash_spaces_loop_end
if c == '# goto delete_hash_spaces_hash
pptoken_copy_and_advance(&in, &out)
goto delete_hash_spaces_loop
:delete_hash_spaces_hash
if out == pptokens goto copy_and_delete_spaces_after_hash ; little edge case
p = out - 2
if *1p != 32 goto copy_and_delete_spaces_after_hash ; no space before ##
; space before #/##
; remove it
out -= 2
*1out = 0
:copy_and_delete_spaces_after_hash
pptoken_copy_and_advance(&in, &out)
pptoken_skip_spaces(&in)
goto delete_hash_spaces_loop
:delete_hash_spaces_loop_end
*1out = 0
free(pptokens2)
close(fd)
return pptokens
:unterminated_comment
compile_error(filename, line_number, .str_unterminated_comment)
:str_unterminated_comment
string Unterminated comment.
byte 0
:unterminated_string
compile_error(filename, line_number, .str_unterminated_string)
:str_unterminated_string
string Unterminated string or character literal.
byte 0
:bad_pptoken
compile_error(filename, line_number, .str_bad_pptoken)
:str_bad_pptoken
string Bad preprocessing token.
byte 0
:no_newline_at_end_of_file
compile_error(filename, 0, .str_no_newline_at_end_of_file)
:str_no_newline_at_end_of_file
string No newline at end of file.
byte 0
; can the given character appear in a C89 ppnumber?
function is_ppnumber_char
argument c
if c == '. goto return_1
if c < '0 goto return_0
if c <= '9 goto return_1
if c < 'A goto return_0
if c <= 'Z goto return_1
if c == '_ goto return_1
if c < 'a goto return_0
if c <= 'z goto return_1
goto return_0
function print_pptokens
argument pptokens
local p
p = pptokens
:print_pptokens_loop
if *1p == 0 goto print_pptokens_loop_end
; putc('{)
puts(p)
; putc('})
p += strlen(p)
p += 1
goto print_pptokens_loop
:print_pptokens_loop_end
putc(10)
return
function pptoken_copy_and_advance
argument p_in
argument p_out
local in
local out
in = *8p_in
out = *8p_out
out = strcpy(out, in)
in = memchr(in, 0)
*8p_in = in + 1
*8p_out = out + 1
return
function pptoken_skip
argument p_in
local in
in = *8p_in
in = memchr(in, 0)
*8p_in = in + 1
return
; skip any space tokens here
function pptoken_skip_spaces
argument p_in
local in
in = *8p_in
:pptoken_skip_spaces_loop
if *1in != 32 goto pptoken_skip_spaces_loop_end
pptoken_skip(&in)
goto pptoken_skip_spaces_loop
:pptoken_skip_spaces_loop_end
*8p_in = in
return
function pptoken_skip_to_newline
argument p_in
local in
in = *8p_in
:pptoken_skip_to_newline_loop
if *1in == 10 goto pptoken_skip_to_newline_end
pptoken_skip(&in)
goto pptoken_skip_to_newline_loop
:pptoken_skip_to_newline_end
*8p_in = in
return
; phase 4:
; Preprocessing directives are executed and macro invocations are expanded.
; A #include preprocessing directive causes the named header or source file to be processed from phase 1 through phase 4, recursively.
function translation_phase_4
argument filename
argument input
local output
local in
local out
local p
local c
local b
local macro_name
local line_number
output = malloc(16000000)
out = output
in = input
line_number = 0
:phase4_line
line_number += 1
c = *1in
if c == 0 goto phase4_end
if c == '# goto pp_directive ; NOTE: ## cannot appear at the start of a line
:process_pptoken
c = *1in
if c == 10 goto phase4_next_line
b = isdigit(c)
if b != 0 goto phase4_next_pptoken
b = isalnum_or_underscore(c)
if b != 0 goto phase4_try_replacements
; (fallthrough)
:phase4_next_pptoken
pptoken_copy_and_advance(&in, &out)
goto process_pptoken
:phase4_next_line
pptoken_copy_and_advance(&in, &out)
goto phase4_line
:phase4_try_replacements
macro_replacement(filename, line_number, &in, &out)
goto process_pptoken
:pp_directive
pptoken_skip(&in) ; skip #
pptoken_skip_spaces(&in)
c = *1in
if c == 10 goto phase4_next_line ; "null directive" C89 § 3.8.7
b = str_equals(in, .str_error)
if b != 0 goto pp_directive_error
b = str_equals(in, .str_define)
if b != 0 goto pp_directive_define
b = str_equals(in, .str_undef)
if b != 0 goto pp_directive_undef
b = str_equals(in, .str_pragma)
if b != 0 goto pp_directive_pragma
b = str_equals(in, .str_line)
if b != 0 goto pp_directive_line
goto unrecognized_directive
:pp_directive_error
fputs(2, filename)
fputc(2, ':)
fputn(2, line_number)
fputs(2, .str_directive_error)
exit(1)
:pp_directive_line
; at this stage, we just turn #line directives into a nicer format:
; {$line_number filename} e.g. {$77 main.c}
local new_line_number
pptoken_skip(&in)
pptoken_skip_spaces(&in)
new_line_number = stoi(in)
new_line_number -= 1 ; #line directive applies to the following line
*1out = '$
out += 1
; copy line number
p = itos(new_line_number)
out = strcpy(out, p)
*1out = 32
out += 1
pptoken_skip(&in)
pptoken_skip_spaces(&in)
if *1in == 10 goto ppdirective_line_no_filename
if *1in != '" goto bad_line_directive
; copy filename
in += 1
filename = out
out = memccpy(out, in, '")
*1out = 0
out += 1
goto ppdirective_line_cont
:ppdirective_line_no_filename
out = strcpy(out, filename)
out += 1
:ppdirective_line_cont
pptoken_skip_to_newline(&in)
line_number = new_line_number
goto process_pptoken
:pp_directive_undef
pptoken_skip(&in)
pptoken_skip_spaces(&in)
macro_name = in
pptoken_skip(&in)
pptoken_skip_spaces(&in)
if *1in != 10 goto bad_undef
p = look_up_object_macro(macro_name)
if p == 0 goto undef_not_object
p -= 2
*1p = '@ ; replace last character of macro name with @ to "undefine" it
:undef_not_object
p = look_up_function_macro(macro_name)
if p == 0 goto undef_not_function
p -= 2
*1p = '@
:undef_not_function
goto process_pptoken
:pp_directive_define
pptoken_skip(&in)
pptoken_skip_spaces(&in)
macro_name = in
pptoken_skip(&in)
pptoken_skip_spaces(&in)
c = *1in
if c == '( goto function_macro_definition
; it's an object-like macro, e.g. #define X 47
b = look_up_object_macro(macro_name)
if b != 0 goto macro_redefinition
p = object_macros + object_macros_size
; copy name
p = strcpy(p, macro_name)
p += 1
; copy contents
memccpy_advance(&p, &in, 10) ; copy until newline
*1p = 255 ; replace newline with special "macro end" character
p += 1
object_macros_size = p - object_macros
goto phase4_next_line
:function_macro_definition
; a function-like macro, e.g. #define JOIN(a,b) a##b
local param_names
local param_name
local param_idx
b = look_up_function_macro(macro_name)
if b != 0 goto macro_redefinition
param_names = malloc(4000)
pptoken_skip(&in) ; skip opening parenthesis
pptoken_skip_spaces(&in)
param_name = param_names
:macro_params_loop
c = *1in
if c == 10 goto phase4_missing_closing_bracket
b = isalpha_or_underscore(c)
if b == 0 goto bad_macro_params
param_name = strcpy(param_name, in)
param_name += 1
pptoken_skip(&in)
pptoken_skip_spaces(&in)
c = *1in
if c == ') goto macro_params_loop_end
if c != ', goto bad_macro_params
pptoken_skip(&in) ; skip ,
pptoken_skip_spaces(&in)
goto macro_params_loop
:macro_params_loop_end
pptoken_skip(&in) ; skip )
pptoken_skip_spaces(&in)
p = function_macros + function_macros_size
p = strcpy(p, macro_name)
p += 1
:fmacro_body_loop
if *1in == 10 goto fmacro_body_loop_end
param_name = param_names
param_idx = 1
; check if this token matches any of the parameter names
:fmacro_param_check_loop
if *1param_name == 0 goto fmacro_param_check_loop_end
b = str_equals(in, param_name)
if b != 0 goto fmacro_param_match
param_name = memchr(param_name, 0)
param_name += 1
param_idx += 1
goto fmacro_param_check_loop
:fmacro_param_check_loop_end
; it's not a parameter; just copy it out
p = strcpy(p, in)
p += 1
pptoken_skip(&in)
goto fmacro_body_loop
:fmacro_param_match
; a match!
*1p = param_idx ; store the parameter index (1 = first argument) as a pptoken
p += 2
pptoken_skip(&in)
goto fmacro_body_loop
:fmacro_body_loop_end
*1p = 255
p += 1
function_macros_size = p - function_macros
free(param_names)
goto phase4_next_line
:pp_directive_pragma
; we don't have any pragmas
compile_warning(filename, line_number, .str_unrecognized_pragma)
pptoken_skip_to_newline(&in)
goto process_pptoken
:str_unrecognized_pragma
string Unrecognized #pragma.
byte 0
:str_directive_error
string : #error
byte 10
byte 0
:phase4_end
return output
:unrecognized_directive
compile_error(filename, line_number, .str_unrecognized_directive)
:str_unrecognized_directive
string Unrecognized preprocessor directive.
byte 0
:macro_redefinition
; @NONSTANDARD:
; technically not an error if it was redefined to the same thing, but it's
; annoying to check for that
compile_error(filename, line_number, .str_macro_redefinition)
:str_macro_redefinition
string Macro redefinition.
byte 0
:phase4_missing_closing_bracket
compile_error(filename, line_number, .str_missing_closing_bracket)
:bad_macro_params
compile_error(filename, line_number, .str_bad_macro_params)
:str_bad_macro_params
string Bad macro parameter list.
byte 0
:bad_undef
compile_error(filename, line_number, .str_bad_undef)
:str_bad_undef
string Bad #undef.
byte 0
:bad_line_directive
compile_error(filename, line_number, .str_bad_line_directive)
:str_bad_line_directive
string Bad #line.
byte 0
; returns a pointer to the replacement pptokens, or 0 if this macro is not defined
function look_up_macro
argument macros
argument name
local p
local b
p = macros
:macro_lookup_loop
if *1p == 0 goto return_0
b = str_equals(p, name)
if b != 0 goto macro_lookup_loop_end
; advance to next macro
p = memchr(p, 255)
p += 1
goto macro_lookup_loop
:macro_lookup_loop_end
p = memchr(p, 0)
p += 1
return p
function look_up_object_macro
argument name
return look_up_macro(object_macros, name)
function look_up_function_macro
argument name
return look_up_macro(function_macros, name)
; replace pptoken(s) at *p_in into *p_out, advancing both
; NOTE: if *p_in starts with a function-like macro replacement, it is replaced fully,
; otherwise this function only reads 1 token from *p_in
function macro_replacement
argument filename
argument line_number
argument p_in
argument p_out
; "banned" macros prevent #define x x from being a problem
; C89 § 3.8.3.4
; "If the name of the macro being replaced is found during this scan
; of the replacement list, it is not replaced. Further, if any nested
; replacements encounter the name of the macro being replaced, it is not replaced."
global 2000 dat_banned_objmacros ; 255-terminated array of strings (initialized in main)
local old_banned_objmacros_end
global 2000 dat_banned_fmacros
local old_banned_fmacros_end
local banned_fmacros
local banned_objmacros
local b
local c
local p
local q
local replacement
local in
local out
in = *8p_in
out = *8p_out
banned_objmacros = &dat_banned_objmacros
banned_fmacros = &dat_banned_fmacros
old_banned_objmacros_end = memchr(banned_objmacros, 255)
old_banned_fmacros_end = memchr(banned_fmacros, 255)
p = in
pptoken_skip(&p)
pptoken_skip_spaces(&p)
if *1p == '( goto fmacro_replacement
p = banned_objmacros
:check_banned_objmacros_loop
if *1p == 255 goto check_banned_objmacros_loop_end
b = str_equals(in, p)
if b != 0 goto no_replacement
p = memchr(p, 0)
p += 1
goto check_banned_objmacros_loop
:check_banned_objmacros_loop_end
replacement = look_up_object_macro(in)
if replacement == 0 goto no_replacement
; add this to list of banned macros
p = strcpy(old_banned_objmacros_end, in)
p += 1
*1p = 255
p = replacement
pptoken_skip(&in) ; skip macro
:objreplace_loop
if *1p == 255 goto done_replacement
macro_replacement(filename, line_number, &p, &out)
goto objreplace_loop
:fmacro_replacement
p = banned_fmacros
:check_banned_fmacros_loop
if *1p == 255 goto check_banned_fmacros_loop_end
b = str_equals(in, p)
if b != 0 goto no_replacement
p = memchr(p, 0)
p += 1
goto check_banned_fmacros_loop
:check_banned_fmacros_loop_end
replacement = look_up_function_macro(in)
if replacement == 0 goto no_replacement
local macro_name
macro_name = in
pptoken_skip(&in) ; skip macro name
pptoken_skip_spaces(&in)
pptoken_skip(&in) ; skip opening bracket
if *1in == ') goto empty_fmacro_invocation
local arguments
local fmacro_out
local fmacro_out_start
arguments = malloc(4000)
fmacro_out_start = malloc(8000) ; direct fmacro output. this will need to be re-scanned for macros
fmacro_out = fmacro_out_start
; store the arguments (separated by 255-characters)
p = arguments
:fmacro_arg_loop
b = fmacro_arg_end(filename, line_number, in)
b -= in
memcpy(p, in, b) ; copy the argument to its proper place
p += b
in += b ; skip argument
c = *1in
in += 2 ; skip , or )
pptoken_skip_spaces(&in)
*1p = 255
p += 1
if c == ', goto fmacro_arg_loop
*1p = 255 ; use an additional 255-character to mark the end (note: macro arguments may not be empty)
; print arguments:
; p += 1
; p -= arguments
; syscall(1, 1, arguments, p)
p = replacement
:freplace_loop
if *1p == 255 goto freplace_loop_end
if *1p < 32 goto fmacro_argument
if *1p == '# goto freplace_hash_operator
pptoken_copy_and_advance(&p, &fmacro_out)
goto freplace_loop
:freplace_hash_operator
; handle paste and stringify operators
; NOTE: we already ensured that there's no spaces following #,
; and no spaces surrounding ## in split_into_preprocessing_tokens
p += 1
if *1p == '# goto freplace_hashhash_operator
; stringify operator
p += 1 ; skip null separator following #
q = fmacro_get_arg(filename, line_number, arguments, *1p)
*1fmacro_out = '"
fmacro_out += 1
; @NONSTANDARD: this doesn't work if the argument contains " or \
:fmacro_stringify_loop
c = *1q
q += 1
if c == 255 goto fmacro_stringify_loop_end
if c == 0 goto fmacro_stringify_loop
*1fmacro_out = c
fmacro_out += 1
goto fmacro_stringify_loop
:fmacro_stringify_loop_end
*1fmacro_out = '"
fmacro_out += 1
*1fmacro_out = 0
fmacro_out += 1
p += 2 ; skip arg idx & null separator
goto freplace_loop
:freplace_hashhash_operator
; the paste operator (e.g. #define JOIN(a,b) a##b)
; wow! surprisingly simple!
fmacro_out -= 1
pptoken_skip(&p)
goto freplace_loop
:freplace_loop_end
; add this to list of banned macros
; it's important that we do this now and not earlier because this is valid:
; #define f(x) x x
; const char *s = f(f("a")); /* this preprocesses to s = "a" "a" "a" "a" */
p = strcpy(old_banned_fmacros_end, macro_name)
p += 1
*1p = 255
fmacro_out = fmacro_out_start
:frescan_loop
if *1fmacro_out == 0 goto frescan_loop_end
macro_replacement(filename, line_number, &fmacro_out, &out)
goto frescan_loop
:frescan_loop_end
free(arguments)
free(fmacro_out_start)
goto done_replacement
:fmacro_argument
q = p + 3 ; skip these characters: arg idx, null separator, first '#'
if *1q == '# goto fmacro_argument_no_rescan ; this argument is immediately followed by ## so it shouldn't be scanned for replacements
q = p - 2 ; skip these characters: null separator, second '#'
if *1q == '# goto fmacro_argument_no_rescan ; this argument is immediately preceded by ##
; write argument to *fmacro_out, performing any necessary macro substitutions
q = fmacro_get_arg(filename, line_number, arguments, *1p)
:fmacro_arg_replace_loop
macro_replacement(filename, line_number, &q, &fmacro_out)
if *1q != 255 goto fmacro_arg_replace_loop
p += 2 ; skip arg idx & null separator
goto freplace_loop
:fmacro_argument_no_rescan
q = fmacro_get_arg(filename, line_number, arguments, *1p)
fmacro_out = memccpy(fmacro_out, q, 255)
*1fmacro_out = 0
p += 2 ; skip arg idx & null separator
goto freplace_loop
:no_replacement
pptoken_copy_and_advance(&in, &out)
; (fallthrough)
:done_replacement
*8p_in = in
*8p_out = out
; unban any macros we just banned
*1old_banned_objmacros_end = 255
*1old_banned_fmacros_end = 255
return
:empty_fmacro_invocation
compile_error(filename, line_number, .str_empty_fmacro_invocation)
:str_empty_fmacro_invocation
string No arguments provided to function-like macro.
byte 0
function fmacro_get_arg
argument filename
argument line_number
argument arguments
argument arg_idx
:fmacro_argfind_loop
if *1arguments == 255 goto fmacro_too_few_arguments
if arg_idx == 1 goto fmacro_arg_found
arguments = memchr(arguments, 255)
arguments += 1
arg_idx -= 1
goto fmacro_argfind_loop
:fmacro_arg_found
return arguments
:fmacro_too_few_arguments
compile_error(filename, line_number, .str_fmacro_too_few_arguments)
:str_fmacro_too_few_arguments
string Too few arguments to function-like macro.
byte 0
function fmacro_arg_end
argument filename
argument line_number
argument in
local bracket_depth
bracket_depth = 1
:fmacro_arg_end_loop
if *1in == 0 goto fmacro_missing_closing_bracket
if *1in == '( goto fmacro_arg_opening_bracket
if *1in == ') goto fmacro_arg_closing_bracket
if *1in == ', goto fmacro_arg_potential_end
pptoken_skip(&in)
goto fmacro_arg_end_loop
:fmacro_arg_potential_end
if bracket_depth == 1 goto fmacro_arg_end_loop_end
pptoken_skip(&in)
goto fmacro_arg_end_loop
:fmacro_arg_opening_bracket
bracket_depth += 1
pptoken_skip(&in)
goto fmacro_arg_end_loop
:fmacro_arg_closing_bracket
bracket_depth -= 1
if bracket_depth == 0 goto fmacro_arg_end_loop_end
pptoken_skip(&in)
goto fmacro_arg_end_loop
:fmacro_arg_end_loop_end
return in
:fmacro_missing_closing_bracket
compile_error(filename, line_number, .str_missing_closing_bracket)
function print_object_macros
print_macros(object_macros)
return
function print_function_macros
print_macros(function_macros)
return
function print_macros
argument macros
local p
local c
p = macros
:print_macros_loop
if *1p == 0 goto return_0 ; done!
puts(p)
putc(':)
putc(32)
p = memchr(p, 0)
p += 1
:print_replacement_loop
c = *1p
if c == 255 goto print_replacement_loop_end
if c < 32 goto print_macro_param
putc('{)
puts(p)
putc('})
p = memchr(p, 0)
p += 1
goto print_replacement_loop
:print_macro_param
putc('{)
putc('#)
putn(c)
putc('})
p += 2
goto print_replacement_loop
:print_replacement_loop_end
p += 1
fputc(1, 10)
goto print_macros_loop
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