/*******************************************************************/

/*  slibtool: a skinny libtool implementation, written in C        */

/*  Copyright (C) 2016--2024  SysDeer Technologies, LLC            */

/*  Released under the Standard MIT License; see COPYING.SLIBTOOL. */

/*******************************************************************/

#include <slibtool/slibtool.h>

#include "slibtool_ar_impl.h"

#include "slibtool_driver_impl.h"

#include "slibtool_snprintf_impl.h"

#include "slibtool_errinfo_impl.h"

static int slbt_ar_dlsyms_define_by_type(

	int                                 fdout,

	const char *                        arname,

	struct slbt_archive_meta_impl *     mctx,

	const char *                        desc,

	const char                          stype)

{

	uint64_t idx;

	uint64_t nsyms = 0;

	for (idx=0; idx<mctx->armaps.armap_nsyms; idx++)

		if (mctx->syminfv[idx]->ar_symbol_type[0] == stype)

			nsyms++;

	if (nsyms == 0)

		return 0;

	if (slbt_dprintf(fdout,"/* %s (%s) */\n",desc,arname) < 0)

		return SLBT_SYSTEM_ERROR(mctx->dctx,0);

	for (idx=0; idx<mctx->armaps.armap_nsyms; idx++)

		if (mctx->syminfv[idx]->ar_symbol_type[0] == stype)

			if (slbt_dprintf(fdout,

					(stype == 'T')

						? "extern int %s();\n"

						: "extern char %s[];\n",

					mctx->syminfv[idx]->ar_symbol_name) < 0)

				return SLBT_SYSTEM_ERROR(mctx->dctx,0);

	if (slbt_dprintf(fdout,"\n") < 0)

		return SLBT_SYSTEM_ERROR(mctx->dctx,0);

	return 0;

}

static int slbt_ar_dlsyms_get_max_len_by_type(

	int                                 mlen,

	struct slbt_archive_meta_impl *     mctx,

	const char                          stype)

{

	int      len;

	uint64_t idx;

	for (idx=0; idx<mctx->armaps.armap_nsyms; idx++)

		if (mctx->syminfv[idx]->ar_symbol_type[0] == stype)

			if ((len = strlen(mctx->syminfv[idx]->ar_symbol_name)) > mlen)

				mlen = len;

	return mlen;

}

static int slbt_ar_dlsyms_add_by_type(

	int                                 fdout,

	struct slbt_archive_meta_impl *     mctx,

	const char *                        fmt,

	const char                          stype,

	char                                (*namebuf)[4096])

{

	uint64_t  idx;

	uint64_t  nsyms;

	char *    symname;

	nsyms   = 0;

	symname = *namebuf;

	for (idx=0; idx<mctx->armaps.armap_nsyms; idx++)

		if (mctx->syminfv[idx]->ar_symbol_type[0] == stype)

			nsyms++;

	if (nsyms == 0)

		return 0;

	if (slbt_dprintf(fdout,"\n") < 0)

		return SLBT_SYSTEM_ERROR(mctx->dctx,0);

	for (idx=0; idx<mctx->armaps.armap_nsyms; idx++) {

		if (mctx->syminfv[idx]->ar_symbol_type[0] == stype) {

			if (slbt_snprintf(symname,sizeof(*namebuf),

					"%s\",",

					mctx->syminfv[idx]->ar_symbol_name) < 0)

				return SLBT_SYSTEM_ERROR(mctx->dctx,0);

			if (slbt_dprintf(fdout,fmt,

					symname,

					(stype == 'T') ? "&" : "",

					mctx->syminfv[idx]->ar_symbol_name) < 0)

				return SLBT_NESTED_ERROR(mctx->dctx);

		}

	}

	return 0;

}

static int slbt_ar_output_dlsyms_impl(

	int                                 fdout,

	const struct slbt_driver_ctx *      dctx,

	struct slbt_archive_ctx **          arctxv,

	const char *                        dsounit)

{

	int                                 ret;

	int                                 idx;

	unsigned                            len;

	unsigned                            cmp;

	const char *                        arname;

	const char *                        soname;

	struct slbt_archive_ctx *           actx;

	struct slbt_archive_ctx **          parctx;

	struct slbt_archive_ctx_impl *      ictx;

	struct slbt_archive_meta_impl *     mctx;

	const struct slbt_source_version *  verinfo;

	char                                dlsymfmt[32];

	char                                cline[6][73];

	char                                symname[4096];

	/* init */

	actx    = arctxv[0];

	verinfo = slbt_api_source_version();

	/* preamble */

	memset(cline[0],'*',72);

	memset(cline[1],' ',72);

	memset(cline[2],' ',72);

	memset(cline[3],' ',72);

	memset(cline[4],'*',72);

	memset(cline[5],0,72);

	cline[5][0] = '\n';

	len = snprintf(&cline[1][3],72,

		"backward-compatible dlsym table");

	cline[1][3+len] = ' ';

	len = snprintf(&cline[2][3],72,

		"Generated by %s (slibtool %d.%d.%d)",

		dctx->program,

		verinfo->major,verinfo->minor,verinfo->revision);

	cline[2][3+len] = ' ';

	len = snprintf(&cline[3][3],72,

		"[commit reference: %s]",

		verinfo->commit);

	cline[3][3+len] = ' ';

	for (idx=0; idx<5; idx++) {

		cline[idx][0] = '/';

		cline[idx][1] = '*';

		cline[idx][70] = '*';

		cline[idx][71] = '/';

		cline[idx][72] = '\n';

	}

	if (slbt_dprintf(fdout,"%s",&cline[0]) < 0)

		return SLBT_SYSTEM_ERROR(dctx,0);

	if (slbt_dprintf(fdout,

			"#ifdef __cplusplus\n"

			"extern \"C\" {\n"

			"#endif\n\n") < 0)

		return SLBT_SYSTEM_ERROR(dctx,0);

	/* declarations */

	for (parctx=arctxv; *parctx; parctx++) {

		actx   = *parctx;

		ictx   = slbt_get_archive_ictx(actx);

		mctx   = slbt_archive_meta_ictx(ictx->meta);

		if ((arname = strrchr(*actx->path,'/')))

			arname++;

		if (!arname)

			arname = *actx->path;

		ret  = slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Absolute Values",     'A');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: BSS Section",         'B');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Common Section",      'C');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Initialized Data",    'D');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Small Globals",       'G');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Indirect References", 'I');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Read-Only Section",   'R');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Small Objects",       'S');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Data Symbols: Weak Symbols",        'W');

		ret |= slbt_ar_dlsyms_define_by_type(fdout,arname,mctx,"Text Section: Public Interfaces",   'T');

		if (ret < 0)

			return SLBT_NESTED_ERROR(dctx);

	}

	/* vtable struct definition */

	if (slbt_dprintf(fdout,

			"/* name-address Public ABI struct definition */\n"

			"struct lt_dlsym_symdef {\n"

			"\tconst char *   dlsym_name;\n"

			"\tvoid *         dlsym_addr;\n"

			"};\n\n") < 0)

		return SLBT_NESTED_ERROR(dctx);

	soname = (strcmp(dsounit,"@PROGRAM@")) ? dsounit : "_PROGRAM_";

	if (slbt_dprintf(fdout,

			"/* dlsym vtable */\n"

			"extern const struct lt_dlsym_symdef "

			"lt_%s_LTX_preloaded_symbols[];\n\n"

			"const struct lt_dlsym_symdef "

			"lt_%s_LTX_preloaded_symbols[] = {\n",

			soname,soname) < 0)

		return SLBT_NESTED_ERROR(dctx);

	/* align dlsym_name and dlsym_addr columsn (because we can) */

	for (parctx=arctxv,len=0; *parctx; parctx++) {

		actx = *parctx;

		ictx = slbt_get_archive_ictx(actx);

		mctx = slbt_archive_meta_ictx(ictx->meta);

		if ((arname = strrchr(*actx->path,'/')))

			arname++;

		if (!arname)

			arname = *actx->path;

		if (len < (cmp = strlen(arname)))

			len = cmp;

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'A');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'B');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'C');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'D');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'G');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'I');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'R');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'S');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'T');

		len  = slbt_ar_dlsyms_get_max_len_by_type(len,mctx,'W');

	}

	/* quote, comma */

	len += 2;

	if (len >= sizeof(symname))

		return SLBT_CUSTOM_ERROR(

			dctx,

			SLBT_ERR_FLOW_ERROR);

	/* aligned print format */

	snprintf(dlsymfmt,sizeof(dlsymfmt),"\t{\"%%-%ds %%s%%s},\n",len);

	/* dso unit */

	if (slbt_snprintf(symname,sizeof(symname),"%s\",",dsounit) < 0)

		return SLBT_SYSTEM_ERROR(dctx,0);

	if (slbt_dprintf(fdout,dlsymfmt,symname,"","0") < 0)

		return SLBT_NESTED_ERROR(dctx);

	/* (-dlopen force) */

	if (!arctxv[0]->meta->a_memberv)

		if (!strcmp(*arctxv[0]->path,"@PROGRAM@"))

			arctxv++;

	/* at long last */

	for (parctx=arctxv; *parctx; parctx++) {

		actx = *parctx;

		ictx = slbt_get_archive_ictx(actx);

		mctx = slbt_archive_meta_ictx(ictx->meta);

		if ((arname = strrchr(*actx->path,'/')))

			arname++;

		if (!arname)

			arname = *actx->path;

		if (slbt_dprintf(fdout,"\n") < 0)

			return SLBT_NESTED_ERROR(mctx->dctx);

		if (slbt_snprintf(symname,sizeof(symname),"%s\",",arname) < 0)

			return SLBT_SYSTEM_ERROR(mctx->dctx,0);

		if (slbt_dprintf(fdout,dlsymfmt,symname,"","0") < 0)

			return SLBT_NESTED_ERROR(mctx->dctx);

		ret  = slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'A',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'B',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'C',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'D',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'G',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'I',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'R',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'S',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'S',&symname);

		ret |= slbt_ar_dlsyms_add_by_type(fdout,mctx,dlsymfmt,'T',&symname);

		if (ret < 0)

			return SLBT_NESTED_ERROR(dctx);

	}

	/* null-terminate the vtable */

	if (slbt_dprintf(fdout,"\n\t{%d,%*c%d}\n",0,len,' ',0) < 0)

		return SLBT_NESTED_ERROR(mctx->dctx);

	/* close vtable, wrap translation unit */

	if (slbt_dprintf(fdout,

			"};\n\n"

			"#ifdef __cplusplus\n"

			"}\n"

			"#endif\n") < 0)

		return SLBT_SYSTEM_ERROR(dctx,0);

	return 0;

}

static int slbt_ar_create_dlsyms_impl(

	struct slbt_archive_ctx **        arctxv,

	const char *                      dlunit,

	const char *                      path,

	mode_t                            mode)

{

	int                               ret;

	struct slbt_archive_ctx **        actx;

	struct slbt_exec_ctx *            ectx;

	struct slbt_archive_meta_impl *   mctx;

	const struct slbt_driver_ctx *    dctx;

	struct slbt_fd_ctx                fdctx;

	int                               fdout;

	mctx = slbt_archive_meta_ictx(arctxv[0]->meta);

	dctx = mctx->dctx;

	ectx = 0;

	if (slbt_lib_get_driver_fdctx(dctx,&fdctx) < 0)

		return SLBT_NESTED_ERROR(dctx);

	if (path) {

		if ((fdout = openat(

				fdctx.fdcwd,path,

				O_WRONLY|O_CREAT|O_TRUNC,

				mode)) < 0)

			return SLBT_SYSTEM_ERROR(dctx,path);

	} else {

		fdout = fdctx.fdout;

	}

	for (actx=arctxv; *actx; actx++) {

		mctx = slbt_archive_meta_ictx((*actx)->meta);

		if (!mctx->syminfo && !ectx)

			if (slbt_ectx_get_exec_ctx(dctx,&ectx) < 0)

				return SLBT_NESTED_ERROR(dctx);

		if (!mctx->syminfo)

			if (slbt_ar_update_syminfo(*actx,ectx) < 0)

				return SLBT_NESTED_ERROR(dctx);

	}

	if (ectx)

		slbt_ectx_free_exec_ctx(ectx);

	ret = slbt_ar_output_dlsyms_impl(

		fdout,dctx,arctxv,dlunit);

	if (path) {

		close(fdout);

	}

	return ret;

}

int slbt_ar_create_dlsyms(

	struct slbt_archive_ctx **  arctxv,

	const char *                dlunit,

	const char *                path,

	mode_t                      mode)

{

	return slbt_ar_create_dlsyms_impl(arctxv,dlunit,path,mode);

}