diff options
Diffstat (limited to 'nuttx/binfmt/libnxflat/libnxflat_stack.c')
| -rw-r--r-- | nuttx/binfmt/libnxflat/libnxflat_stack.c | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/nuttx/binfmt/libnxflat/libnxflat_stack.c b/nuttx/binfmt/libnxflat/libnxflat_stack.c new file mode 100644 index 000000000..082a2e05e --- /dev/null +++ b/nuttx/binfmt/libnxflat/libnxflat_stack.c @@ -0,0 +1,224 @@ +/**************************************************************************** + * libnxflat/lib/nxflat_stack.c + * + * Copyright (C) 2009 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <spudmonkey@racsa.co.cr> + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in + * the documentation and/or other materials provided with the + * distribution. + * 3. Neither the name NuttX nor the names of its contributors may be + * used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, + * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS + * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED + * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN + * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE + * POSSIBILITY OF SUCH DAMAGE. + * + ****************************************************************************/ + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <sys/types.h> +#include <debug.h> +#include <errno.h> +#include <nuttx/nxflat.h> + +/**************************************************************************** + * Pre-processor Definitions + ****************************************************************************/ + +/**************************************************************************** + * Private Functions + ****************************************************************************/ + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: nxflat_adjuststacksize + ****************************************************************************/ + +void nxflat_adjuststacksize(struct nxflat_loadinfo_s *load_info, + int argc, int envc, int system_usage) +{ + uint32 total_usage = system_usage; + + /* For argc, we will store the array (argc elements), the argc + * value itself, plus a null pointer. + */ + + total_usage += (argc + 2) * sizeof(uint32); + + /* For envc, we will store the array (envc elements) plus a null + * pointer. + */ + + total_usage += (envc + 1) * sizeof(uint32); + + /* And we will store six additional words described the memory + * layout. + */ + + total_usage += 6 * sizeof(uint32); + + /* Add this to the previously determined stack size */ + + load_info->stack_size += total_usage; +} + +/**************************************************************************** + * Name: nxflat_initstack + * + * Description: + * When we enter the NXFLAT_ loader, it will expect to see a stack frame + * like the following. NOTE: This logic assumes a push down stack + * (i.e., we decrement the stack pointer to go from the "BOTTOM" to + * the "TOP"). + * + * + * TOP->argc Argument count (integer) + * argv[0...(argc-1)] Program arguments (pointers) + * NULL Marks end of arguments + * env[0...N] Environment variables (pointers) + * NULL Marks end of environment variables + * loader ispace Address of loader ISpace (NXFLAT_ header) + * loader dspace Address of loader DSpace + * loader dspace size Size of the allocated loader DSpace + * program ispace Address of program ISpace (NXFLAT_ header) + * program dspace Address of program DSpace + * BOTTOM->program dspace size Size of the allocated program DSpace + * + ****************************************************************************/ + +uint32 nxflat_initstack(struct nxflat_loadinfo_s *prog_load_info, + struct nxflat_loadinfo_s *lib_load_info, + int argc, int envc, char *p) +{ + uint32 *argv; + uint32 *envp; + uint32 *sp; + char dummy; + + /* p points to the beginning of the array of arguments; + * sp points to the "bottom" of a push down stack. + */ + + sp = (uint32*)((-(uint32)sizeof(char*))&(uint32) p); + + /* Place program information on the stack */ + + if (prog_load_info) + { + *sp-- = (uint32)prog_load_info->dspace_size; + *sp-- = (uint32)prog_load_info->dspace; + *sp-- = (uint32)prog_load_info->ispace; + } + else + { + dbg("No program load info provided\n"); + return -EINVAL; + } + + /* Place loader information on the stack */ + + if (lib_load_info) + { + *sp-- = (uint32)lib_load_info->dspace_size; + *sp-- = (uint32)lib_load_info->dspace; + *sp-- = (uint32)lib_load_info->ispace; + } + else + { + *sp-- = (uint32)0; + *sp-- = (uint32)0; + *sp-- = (uint32)0; + } + + /* Allocate space on the stack for the envp array contents + * (including space for a null terminator). + */ + + sp -= envc+1; + envp = sp; + + /* Allocate space on the stack for the argv array contents + * (including space for a null terminator). + */ + + sp -= argc+1; + argv = sp; + + /* Put argc on the stack. sp now points to the "top" of the + * stack as it will be received by the new task. + */ + + *sp-- = (uint32)argc; + + /* Copy argv pointers into the stack frame (terminated with + * a null pointer). + */ + + prog_load_info->arg_start = (uint32)p; + while (argc-->0) + { + /* Put the address of the beginning of the string */ + + *argv++ = (uint32)p; + + /* Search for the end of the string */ + + do + { + dummy = *p++; + } + while (dummy); + } + *argv = (uint32)NULL,argv; + + /* Copy envp pointers into the stack frame (terminated with + * a null pointer). + */ + + prog_load_info->env_start = (uint32)p; + while (envc-->0) + { + /* Put the address of the beginning of the string */ + + *envp++ = (uint32)p; + + /* Search for the end of the string */ + + do + { + dummy = *p++; + } + while (dummy); + } + *envp = (uint32)NULL; + + prog_load_info->env_end = (uint32)p; + + return (uint32)sp; +} + |