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Nasm.c：
case op_depend: /* 生成依赖关系（注意：在-a参数下，该功能无法正确实现） */
{
char *line;
preproc->reset(inname, 0, report_error, evaluate, &nasmlist);
if (outname[0] == '\0')
ofmt->filename(inname, outname, report_error); /* .o 结尾的扩展名或者 nasm.out */
ofile = NULL;
fprintf(stdout, "%s: %s", outname, inname);
while ((line = preproc->getline())) /* 实际处理 */
nasm_free(line);
preproc->cleanup(0);
putc('\n', stdout);
}
break;
preproc.c:
/*
*file : 输入文件名
*apass : 预处理是pass 0
*errfunc : 错误处理函数
*eval : 在 eval.c 中
*listgen : 在 listing.c 中实现
*/
static void
pp_reset(char *file, int apass, efunc errfunc, evalfunc eval, ListGen * listgen)
{
int h;
_error = errfunc;
cstk = NULL;
istk = nasm_malloc(sizeof(Include));
istk->next = NULL;
istk->conds = NULL;
istk->expansion = NULL;
istk->mstk = NULL;
istk->fp = fopen(file, "r");
istk->fname = NULL;
src_set_fname(nasm_strdup(file)); /* 在 nasmlib.c */
src_set_linnum(0); /* 在 nasmlib.c */
istk->lineinc = 1;
if (!istk->fp)
error(ERR_FATAL | ERR_NOFILE, "unable to open input file `%s'", file);
defining = NULL;
for (h = 0; h < NHASH; h++) {
mmacros[h] = NULL;
smacros[h] = NULL;
}
unique = 0;
if (tasm_compatible_mode) {
stdmacpos = stdmac;
} else {
stdmacpos = &stdmac[TASM_MACRO_COUNT];
}
any_extrastdmac = (extrastdmac != NULL);
list = listgen;
evaluate = eval;
pass = apass;
}
在preproc.c文件的 pp_getline 函数中：
…….
line = read_line();
if (line) { /* from the current input file */
line = prepreproc(line);
tline = tokenise(line);
nasm_free(line);
break;
}
/*
* The current file has ended; work down the istk
*/
{
/* 删除一个 Include 节点 */
Include *i = istk;
fclose(i->fp);
if (i->conds)
error(ERR_FATAL, "expected `%%endif' before end of file");
/* only set line and file name if there's a next node */
if (i->next) {
src_set_linnum(i->lineno);
nasm_free(src_set_fname(i->fname));
}
istk = i->next;
list->downlevel(LIST_INCLUDE);
nasm_free(i);
if (!istk)
return NULL;
}
}
/*
* We must expand MMacro parameters and MMacro-local labels
* _before_ we plunge into directive processing, to cope
* with things like `%define something %1' such as STRUC
* uses. Unless we're _defining_ a MMacro, in which case
* those tokens should be left alone to go into the
* definition; and unless we're in a non-emitting
* condition, in which case we don't want to meddle with
* anything.
*/
if (!defining && !(istk->conds && !emitting(istk->conds->state))) /* #define emitting(x) ( (x) == COND_IF_TRUE || (x) == COND_ELSE_TRUE )
* (!istk->conds || COND_IF_TRUE || COND_ELSE_TRUE) && !defining */
tline = expand_mmac_params(tline);
/*
* Check the line to see if it's a preprocessor directive.
*/
if (do_directive(tline) == DIRECTIVE_FOUND) {
continue;
} else if (defining) {
……
在preproc.c 的do_directive 的函数中:
……
case PP_INCLUDE:
tline = tline->next;
skip_white_(tline);
if (!tline || (tline->type != TOK_STRING && tline->type != TOK_INTERNAL_STRING)) {
error(ERR_NONFATAL, "`%%include' expects a file name");
free_tlist(origline);
return DIRECTIVE_FOUND; /* but we did _something_ */
}
if (tline->next)
error(ERR_WARNING, "trailing garbage after `%%include' ignored");
if (tline->type != TOK_INTERNAL_STRING) {
p = tline->text + 1; /* point past the quote to the name */
p[strlen(p) - 1] = '\0'; /* remove the trailing quote */
} else
p = tline->text; /* internal_string is easier */
expand_macros_in_string(&p);
/* 插入istk链表 */
inc = nasm_malloc(sizeof(Include));
inc->next = istk;
inc->conds = NULL;
inc->fp = inc_fopen(p);
inc->fname = src_set_fname(p);
inc->lineno = src_set_linnum(0);
inc->lineinc = 1;
inc->expansion = NULL;
inc->mstk = NULL;
istk = inc;
list->uplevel(LIST_INCLUDE);
free_tlist(origline);
return DIRECTIVE_FOUND;
……
/*
* Open an include file. This routine must always return a valid
* file pointer if it returns - it's responsible for throwing an
* ERR_FATAL and bombing out completely if not. It should also try
* the include path one by one until it finds the file or reaches
* the end of the path.
*/
static FILE *inc_fopen(char *file)
{
FILE *fp;
char *prefix = "", *combine;
IncPath *ip = ipath;
static int namelen = 0;
int len = strlen(file);
while (1) {
combine = nasm_malloc(strlen(prefix) + len + 1);
strcpy(combine, prefix);
strcat(combine, file);
fp = fopen(combine, "r");
if (pass == 0 && fp) {
namelen += strlen(combine) + 1;
if (namelen > 62) {
printf(" \\\n ");
namelen = 2;
}
printf(" %s", combine);
}
nasm_free(combine);
if (fp)
return fp;
if (!ip)
break;
prefix = ip->path;
ip = ip->next;
}
error(ERR_FATAL, "unable to open include file `%s'", file);
return NULL; /* never reached - placate compilers */
}
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