Add helper binary `exec1'

* .gitignore: New files.
* Makefile.in (mostlyclean_dirs): Add libexec, if its Makefile
exists.
* autogen.sh (do_git): Autoreconf in exec as well.
* configure.ac: Configure libexec on Android.
* exec/Makefile.in:
* exec/README:
* exec/config-mips.m4.in:
* exec/config.guess:
* exec/config.h.in:
* exec/config.sub:
* exec/configure:
* exec/configure.ac:
* exec/deps.mk:
* exec/exec.c (MIN, struct exec_open_command)
(struct exec_map_command, struct exec_jump_command)
(write_open_command, write_load_command, process_interpreter_1)
(process_interpreter, process_program_header, insert_args)
(exec_0):
* exec/exec.h (_EXEC_H_, struct elf_header_32)
(struct program_header_32, struct dt_entry_32)
(struct elf_header_64, struct program_header_64)
(struct dt_entry_64, struct exec_tracee):
* exec/exec1.c (main):
* exec/install-sh (scriptversion):
* exec/loader-aarch64.s (_start):
* exec/loader-armeabi.s (_start):
* exec/loader-mips64el.s (__start):
* exec/loader-mipsel.s (__start):
* exec/loader-x86.s (_start):
* exec/loader-x86_64.s (_start):
* exec/mipsel-user.h (_MIPSEL_USER_H_):
* exec/mipsfpu.c (MIPS_ABI_FP_ANY, fpu_reqs, valid_abi_p)
(fp_mode_for_abi, cpu_supports_fr0_p, determine_fpu_mode):
* exec/mipsfpu.h (_MIPSFPU_H_, FP_FR0):
* exec/test.c (print_usage, main):
* exec/trace.c (MAX_TRACEES, aarch64_set_regs, read_memory)
(user_alloca, user_copy, remove_tracee, handle_clone)
(syscall_trap_p, handle_exec, process_system_call, tracing_execve)
(after_fork, find_tracee, exec_waitpid, exec_init): New files.
* java/Makefile.in (CROSS_EXEC_BINS): Add exec1 and
loader.
($(CROSS_EXEC_BINS) &): New target.

1 files changed, 192 insertions, 0 deletions

diff --git a/exec/loader-armeabi.s b/exec/loader-armeabi.s
new file mode 100644
index 00000000000..182ff11ec7a
--- /dev/null
+++ b/exec/loader-armeabi.s
@@ -0,0 +1,192 @@
+@ Copyright (C) 2023 Free Software Foundation, Inc.
+@
+@ This file is part of GNU Emacs.
+@
+@ GNU Emacs is free software: you can redistribute it and/or modify
+@ it under the terms of the GNU General Public License as published
+@ by the Free Software Foundation, either version 3 of the License,
+@ or (at your option) any later version.
+@
+@ GNU Emacs is distributed in the hope that it will be useful, but
+@ WITHOUT ANY WARRANTY; without even the implied warranty of
+@ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+@ General Public License for more details.
+@
+@ You should have received a copy of the GNU General Public License
+@ along with GNU Emacs.  If not, see <https:@www.gnu.org/licenses/>.
+
+	.section .text
+	.global _start
+_start:
+	@mov	r7, #162		@ SYS_nanosleep
+	@adr	r0, timespec		@ req
+	@mov	r1, #0			@ rem
+	@swi	#0			@ syscall
+	mov	r8, sp			@ r8 = sp
+	ldr	r9, [r8], #8		@ r9 = original sp, r8 += 8
+	mov	r14, #-1		@ r14 = secondary fd
+.next_action:
+	ldr	r11, [r8]		@ r11 = action number
+	and	r12, r11, #-17		@ actual action number
+	cmp	r12, #0			@ open file?
+	beq	.open_file		@ open file.
+	cmp	r12, #3			@ jump?
+	beq	.rest_of_exec		@ jump to code.
+	cmp	r12, #4			@ anonymous mmap?
+	beq	.do_mmap_anon		@ anonymous mmap.
+.do_mmap:
+	add	r6, r8, #4		@ r6 = r8 + 4
+	ldm	r6!, {r0, r5}		@ vm_address, file_offset
+	ldm	r6!, {r1, r2}		@ protection, length
+	mov	r3, r1			@ swap
+	lsr	r5, #12			@ divide file offset by page size
+	mov	r1, r2			@ swap
+	mov	r2, r3			@ swap
+	ldm	r6!, {r3, r12}		@ flags, clear
+	tst	r11, #16		@ primary fd?
+	mov	r4, r10			@ primary fd
+	beq	.do_mmap_1
+	mov	r4, r14			@ secondary fd
+.do_mmap_1:
+	mov	r7, #192		@ SYS_mmap2
+	swi	#0			@ syscall
+	ldr	r2, [r8, #4]		@ vm_address
+	cmp	r2, r0			@ rc == vm_address?
+	bne	.perror
+	add	r0, r1, r2		@ r0 = length + vm_address
+	sub	r3, r0, r12		@ r3 = r0 - clear
+	mov	r1, #0			@ r1 = 0
+.align:
+	cmp	r0, r3			@ r0 == r3?
+	beq	.continue		@ continue
+	tst	r3, #3			@ r3 & 3?
+	bne	.fill32			@ fill aligned
+	strb	r1, [r3], #1		@ fill byte
+	b	.align			@ align again
+.fill32:
+	sub	r2, r0, r3		@ r2 = r0 - r3
+	cmp	r2, #31			@ r2 >= 32?
+	ble	.fillb			@ start filling bytes
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	str	r1, [r3], #4		@ *r3++ = 0
+	b	.fill32
+.fillb:
+	cmp	r0, r3			@ r0 == r3
+	beq	.continue		@ done
+	strb	r1, [r3], #1		@ ((char *) r3)++ = 0
+	b	.fillb
+.continue:
+	add	r8, r8, #28		@ next action
+	b	.next_action
+.do_mmap_anon:
+	add	r6, r8, #4		@ r6 = r8 + 4
+	ldm	r6!, {r0, r5}		@ vm_address, file_offset
+	ldm	r6!, {r1, r2}		@ protection, length
+	mov	r3, r1			@ swap
+	lsr	r5, #12			@ divide file offset by page size
+	mov	r1, r2			@ swap
+	mov	r2, r3			@ swap
+	ldm	r6!, {r3, r12}		@ flags, clear
+	mov	r4, #-1			@ fd
+	b	.do_mmap_1
+.open_file:
+	mov	r7, #5			@ SYS_open
+	add	r0, r8, #4		@ file name
+	mov	r1, #0			@ O_RDONLY
+	mov	r2, #0			@ mode
+	swi	#0			@ syscall
+	cmp	r0, #-1			@ r0 <= -1?
+	ble	.perror
+	add	r8, r8, #4		@ r8 = start of string
+.nextc:
+	ldrb	r1, [r8], #1		@ b = *r0++
+	cmp	r1, #0			@ b?
+	bne	.nextc			@ next character
+	add	r8, r8, #3		@ round up r8
+	and	r8, r8, #-4		@ mask for round, set r8
+	tst	r11, #16		@ primary fd?
+	bne	.secondary		@ secondary fd
+	mov	r10, r0			@ primary fd
+	b	.next_action		@ next action
+.secondary:
+	mov	r14, r0			@ secondary fd
+	b	.next_action		@ next action
+.perror:
+	mov	r7, #1			@ SYS_exit
+	mvn	r0, r0			@ r0 = ~r0
+	add	r0, r0, #1		@ r0 += 1
+	swi	#0
+.rest_of_exec:
+	mov	r7, r9			@ r7 = original SP
+	ldr	r6, [r7]		@ argc
+	add	r6, r6, #2		@ argc + 2
+	lsl	r6, r6, #2		@ argc *= 4
+	add	r7, r7, r6		@ now past argv
+.skipenv:
+	ldr	r6, [r7], #4		@ r6 = *r7++
+	cmp	r6, #0			@ r6?
+	bne	.skipenv		@ r6?
+.one_auxv:
+	ldr	r6, [r7], #8		@ r6 = *r7, r7 += 2
+	cmp	r6, #0			@ !r6?
+	beq	.cleanup		@ r6?
+	cmp	r6, #3			@ is AT_PHDR?
+	beq	.replace_phdr		@ replace
+	cmp	r6, #4			@ is AT_PHENT?
+	beq	.replace_phent		@ replace
+	cmp	r6, #5			@ is AT_PHNUM?
+	beq	.replace_phnum		@ replace
+	cmp	r6, #9			@ is AT_ENTRY?
+	beq	.replace_entry		@ replace
+	cmp	r6, #7			@ is AT_BASE?
+	beq	.replace_base		@ replace
+	b	.one_auxv		@ next auxv
+.replace_phdr:
+	ldr	r6, [r8, #20]		@ at_phdr
+	str	r6, [r7, #-4]		@ store value
+	b	.one_auxv
+.replace_phent:
+	ldr	r6, [r8, #12]		@ at_phent
+	str	r6, [r7, #-4]		@ store value
+	b	.one_auxv
+.replace_phnum:
+	ldr	r6, [r8, #16]		@ at_phnum
+	str	r6, [r7, #-4]		@ store value
+	b	.one_auxv
+.replace_entry:
+	ldr	r6, [r8, #8]		@ at_entry
+	str	r6, [r7, #-4]		@ store value
+	b	.one_auxv
+.replace_base:
+	ldr	r6, [r8, #24]		@ at_base
+	str	r6, [r7, #-4]		@ store value
+	b	.one_auxv
+.cleanup:
+	cmp	r14, #-1		@ secondary fd set?
+	bne	.cleanup1		@ not set
+	mov	r7, #6			@ SYS_close
+	mov	r0, r14			@ secondary fd
+	swi	#0			@ syscall
+.cleanup1:
+	mov	r7, #6			@ SYS_close
+	mov	r0, r10			@ primary fd
+	swi	#0			@ syscall
+.enter:
+	mov	sp, r9			@ restore original SP
+	mov	r0, #0			@ clear rtld_fini
+	ldr	r1, [r8, #4]		@ branch to code
+	bx	r1
+
+timespec:
+	.long 10
+	.long 10
+
+@ Local Variables:
+@ asm-comment-char: 64
+@ End: