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int main(int argc, char **argv)
...{
pass0 = 1;
want_usage = terminate_after_phase = FALSE;
report_error = report_error_gnu; /**//* 设置报错函数句柄（感觉很有模块化的思想） */
nasm_set_malloc_error(report_error); /**//* nasmlib.c,对nasm_malloc_error赋值 */
offsets = raa_init(); /**//* 初始化struct RAA（建立树叶节点(貌似)） */
forwrefs = saa_init((long)sizeof(struct forwrefinfo)); /**//* 建立链表头，貌似 */
preproc = &nasmpp; /**//* 建立预处理函数,prepro.c（感觉很有模块化的思想） */
operating_mode = op_normal; /**//* 默认是预处理和汇编 */
error_file = stderr; /**//* 错误输出文件 */
seg_init();
register_output_formats(); /**//* outform.c,判断nasm是否有支持输出文件格式，如果没有，出错,如果有的话，返回默认的输出格式，默认是of_bin格式 */
parse_cmdline(argc, argv); /**//* 参数分析 */
if (terminate_after_phase) ...{ /**//* 判断在上面的处理过程中是否有发现错误，如果有，则退出 */
if (want_usage)
usage();
return 1;
}
/**//* If debugging info is disabled, suppress any debug calls */
if (!using_debug_info)
ofmt->current_dfmt = &null_debug_form; /**//* 暂不解释*/
if (ofmt->stdmac)
pp_extra_stdmac(ofmt->stdmac); /**//* 在preproc.c，将stdmac赋值给prepro.c里面的值进行处理，可能是为了更好的模块化吧？ */
parser_global_info(ofmt, &location); /**//* parser.c,ofmt在之前设置默认值，默认值在register_output_formats()给出 */
eval_global_info(ofmt, lookup_label, &location); /**//* 在eval.c中，ofmt同上，lookup_label在labels.c中 */
/**//* location:Pointer to current line's segment,offset,由于模块化的原因，parser.c与eval.c中均有静态指针指向nasm.c中的loaction*/
/**//* define some macros dependent of command-line */
...{
char temp[64];
snprintf(temp, sizeof(temp), "__OUTPUT_FORMAT__=%s ",
ofmt->shortname); /**//* nasm将要处理的可执行文件格式 */
pp_pre_define(temp); /**//* preproc.c,功能??? */
}
/**//* 一下这一部分将结合接下来的分析进行，暂时不处理 */
switch (operating_mode) ...{
case op_depend: /**//* 生成依赖关系 */
...{
char *line;
preproc->reset(inname, 0, report_error, evaluate, &nasmlist);
if (outname[0] == '')
ofmt->filename(inname, outname, report_error);
ofile = NULL;
fprintf(stdout, "%s: %s", outname, inname);
while ((line = preproc->getline()))
nasm_free(line);
preproc->cleanup(0);
putc(' ', stdout);
}
break;
case op_preprocess: /**//* 仅仅进行预处理 */
...{
char *line;
char *file_name = NULL;
long prior_linnum = 0;
int lineinc = 0;
if (*outname) ...{
ofile = fopen(outname, "w");
if (!ofile)
report_error(ERR_FATAL | ERR_NOFILE,
"unable to open output file `%s'",
outname);
} else
ofile = NULL;
location.known = FALSE;
/**//* pass = 1; */
preproc->reset(inname, 2, report_error, evaluate, &nasmlist);
while ((line = preproc->getline())) ...{
/**//*
* We generate %line directives if needed for later programs
*/
long linnum = prior_linnum += lineinc;
int altline = src_get(&linnum, &file_name);
if (altline) ...{
if (altline == 1 && lineinc == 1)
nasm_fputs("", ofile);
else ...{
lineinc = (altline != -1 || lineinc != 1);
fprintf(ofile ? ofile : stdout,
"%%line %ld+%d %s ", linnum, lineinc,
file_name);
}
prior_linnum = linnum;
}
nasm_fputs(line, ofile);
nasm_free(line);
}
nasm_free(file_name);
preproc->cleanup(0);
if (ofile)
fclose(ofile);
if (ofile && terminate_after_phase)
remove(outname);
}
break;
case op_normal: /**//* 预处理与编译 */
...{
/**//*
* We must call ofmt->filename _anyway_, even if the user
* has specified their own output file, because some
* formats (eg OBJ and COFF) use ofmt->filename to find out
* the name of the input file and then put that inside the
* file.
*/
ofmt->filename(inname, outname, report_error);
ofile = fopen(outname, "wb");
if (!ofile) ...{
report_error(ERR_FATAL | ERR_NOFILE,
"unable to open output file `%s'", outname);
}
/**//*
* We must call init_labels() before ofmt->init() since
* some object formats will want to define labels in their
* init routines. (eg OS/2 defines the FLAT group)
*/
init_labels();
ofmt->init(ofile, report_error, define_label, evaluate);
assemble_file(inname);
if (!terminate_after_phase) ...{
ofmt->cleanup(using_debug_info);
cleanup_labels();
} else ...{
/**//*
* We had an fclose on the output file here, but we
* actually do that in all the object file drivers as well,
* so we're leaving out the one here.
* fclose (ofile);
*/
remove(outname);
if (listname[0])
remove(listname);
}
}
break;
}
if (want_usage)
usage();
raa_free(offsets); /**//* 删除 raa 数据结构 */
saa_free(forwrefs); /**//* 删除 saa 数据结构 */
eval_cleanup(); /**//* eval.c,释放编译过程产生的资源 */
nasmlib_cleanup(); /**//* nasmlib.c,释放编译过程产生的资源 */
if (terminate_after_phase)
return 1;
else
return 0;
}
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