image.c

Go to the documentation of this file.

// SPDX-License-Identifier: GPL-2.0-or-later
 
/***************************************************************************
 *   Copyright (C) 2007 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2007,2008 Øyvind Harboe                                 *
 *   oyvind.harboe@zylin.com                                               *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   Copyright (C) 2009 by Franck Hereson                                  *
 *   franck.hereson@secad.fr                                               *
 *                                                                         *
 *   Copyright (C) 2018 by Advantest                                       *
 *   florian.meister@advantest.com                                         *
 ***************************************************************************/
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include "image.h"
#include "target.h"
#include <helper/log.h>
 
/* convert ELF header field to host endianness */
#define field16(elf, field) \
    ((elf->endianness == ELFDATA2LSB) ? \
    le_to_h_u16((uint8_t *)&field) : be_to_h_u16((uint8_t *)&field))
 
#define field32(elf, field) \
    ((elf->endianness == ELFDATA2LSB) ? \
    le_to_h_u32((uint8_t *)&field) : be_to_h_u32((uint8_t *)&field))
 
#define field64(elf, field) \
    ((elf->endianness == ELFDATA2LSB) ? \
    le_to_h_u64((uint8_t *)&field) : be_to_h_u64((uint8_t *)&field))
 
static int autodetect_image_type(struct image *image, const char *url)
{
    int retval;
    struct fileio *fileio;
    size_t read_bytes;
    uint8_t buffer[9];
 
    /* read the first 9 bytes of image */
    retval = fileio_open(&fileio, url, FILEIO_READ, FILEIO_BINARY);
    if (retval != ERROR_OK)
        return retval;
    retval = fileio_read(fileio, 9, buffer, &read_bytes);
 
    if (retval == ERROR_OK) {
        if (read_bytes != 9)
            retval = ERROR_FILEIO_OPERATION_FAILED;
    }
    fileio_close(fileio);
 
    if (retval != ERROR_OK)
        return retval;
 
    /* check header against known signatures */
    if (strncmp((char *)buffer, ELFMAG, SELFMAG) == 0) {
        LOG_DEBUG("ELF image detected.");
        image->type = IMAGE_ELF;
    } else if ((buffer[0] == ':')   /* record start byte */
        && (isxdigit(buffer[1]))
        && (isxdigit(buffer[2]))
        && (isxdigit(buffer[3]))
        && (isxdigit(buffer[4]))
        && (isxdigit(buffer[5]))
        && (isxdigit(buffer[6]))
        && (buffer[7] == '0')   /* record type : 00 -> 05 */
        && (buffer[8] >= '0') && (buffer[8] < '6')) {
        LOG_DEBUG("IHEX image detected.");
        image->type = IMAGE_IHEX;
    } else if ((buffer[0] == 'S')   /* record start byte */
        && (isxdigit(buffer[1]))
        && (isxdigit(buffer[2]))
        && (isxdigit(buffer[3]))
        && (buffer[1] >= '0') && (buffer[1] < '9')) {
        LOG_DEBUG("S19 image detected.");
        image->type = IMAGE_SRECORD;
    } else
        image->type = IMAGE_BINARY;
 
    return ERROR_OK;
}
 
static int identify_image_type(struct image *image, const char *type_string, const char *url)
{
    if (type_string) {
        if (!strcmp(type_string, "bin"))
            image->type = IMAGE_BINARY;
        else if (!strcmp(type_string, "ihex"))
            image->type = IMAGE_IHEX;
        else if (!strcmp(type_string, "elf"))
            image->type = IMAGE_ELF;
        else if (!strcmp(type_string, "mem"))
            image->type = IMAGE_MEMORY;
        else if (!strcmp(type_string, "s19"))
            image->type = IMAGE_SRECORD;
        else if (!strcmp(type_string, "build"))
            image->type = IMAGE_BUILDER;
        else
            return ERROR_IMAGE_TYPE_UNKNOWN;
    } else
        return autodetect_image_type(image, url);
 
    return ERROR_OK;
}
 
static int image_ihex_buffer_complete_inner(struct image *image,
    char *lpsz_line,
    struct imagesection *section)
{
    struct image_ihex *ihex = image->type_private;
    struct fileio *fileio = ihex->fileio;
    uint32_t full_address;
    uint32_t cooked_bytes;
    bool end_rec = false;
 
    /* we can't determine the number of sections that we'll have to create ahead of time,
     * so we locally hold them until parsing is finished */
 
    size_t filesize;
    int retval;
    retval = fileio_size(fileio, &filesize);
    if (retval != ERROR_OK)
        return retval;
 
    ihex->buffer = malloc(filesize >> 1);
    cooked_bytes = 0x0;
    image->num_sections = 0;
 
    while (!fileio_feof(fileio)) {
        full_address = 0x0;
        section[image->num_sections].private = &ihex->buffer[cooked_bytes];
        section[image->num_sections].base_address = 0x0;
        section[image->num_sections].size = 0x0;
        section[image->num_sections].flags = 0;
 
        while (fileio_fgets(fileio, 1023, lpsz_line) == ERROR_OK) {
            uint32_t count;
            uint32_t address;
            uint32_t record_type;
            uint32_t checksum;
            uint8_t cal_checksum = 0;
            size_t bytes_read = 0;
 
            /* skip comments and blank lines */
            if ((lpsz_line[0] == '#') || (strlen(lpsz_line + strspn(lpsz_line, "\n\t\r ")) == 0))
                continue;
 
            if (sscanf(&lpsz_line[bytes_read], ":%2" SCNx32 "%4" SCNx32 "%2" SCNx32, &count,
                &address, &record_type) != 3)
                return ERROR_IMAGE_FORMAT_ERROR;
            bytes_read += 9;
 
            cal_checksum += (uint8_t)count;
            cal_checksum += (uint8_t)(address >> 8);
            cal_checksum += (uint8_t)address;
            cal_checksum += (uint8_t)record_type;
 
            if (record_type == 0) { /* Data Record */
                if ((full_address & 0xffff) != address) {
                    /* we encountered a nonconsecutive location, create a new section,
                     * unless the current section has zero size, in which case this specifies
                     * the current section's base address
                     */
                    if (section[image->num_sections].size != 0) {
                        image->num_sections++;
                        if (image->num_sections >= IMAGE_MAX_SECTIONS) {
                            /* too many sections */
                            LOG_ERROR("Too many sections found in IHEX file");
                            return ERROR_IMAGE_FORMAT_ERROR;
                        }
                        section[image->num_sections].size = 0x0;
                        section[image->num_sections].flags = 0;
                        section[image->num_sections].private =
                            &ihex->buffer[cooked_bytes];
                    }
                    section[image->num_sections].base_address =
                        (full_address & 0xffff0000) | address;
                    full_address = (full_address & 0xffff0000) | address;
                }
 
                while (count-- > 0) {
                    unsigned value;
                    sscanf(&lpsz_line[bytes_read], "%2x", &value);
                    ihex->buffer[cooked_bytes] = (uint8_t)value;
                    cal_checksum += (uint8_t)ihex->buffer[cooked_bytes];
                    bytes_read += 2;
                    cooked_bytes += 1;
                    section[image->num_sections].size += 1;
                    full_address++;
                }
            } else if (record_type == 1) {  /* End of File Record */
                /* finish the current section */
                image->num_sections++;
 
                /* copy section information */
                image->sections = malloc(sizeof(struct imagesection) * image->num_sections);
                for (unsigned int i = 0; i < image->num_sections; i++) {
                    image->sections[i].private = section[i].private;
                    image->sections[i].base_address = section[i].base_address;
                    image->sections[i].size = section[i].size;
                    image->sections[i].flags = section[i].flags;
                }
 
                end_rec = true;
                break;
            } else if (record_type == 2) {  /* Linear Address Record */
                uint16_t upper_address;
 
                sscanf(&lpsz_line[bytes_read], "%4hx", &upper_address);
                cal_checksum += (uint8_t)(upper_address >> 8);
                cal_checksum += (uint8_t)upper_address;
                bytes_read += 4;
 
                if ((full_address >> 4) != upper_address) {
                    /* we encountered a nonconsecutive location, create a new section,
                     * unless the current section has zero size, in which case this specifies
                     * the current section's base address
                     */
                    if (section[image->num_sections].size != 0) {
                        image->num_sections++;
                        if (image->num_sections >= IMAGE_MAX_SECTIONS) {
                            /* too many sections */
                            LOG_ERROR("Too many sections found in IHEX file");
                            return ERROR_IMAGE_FORMAT_ERROR;
                        }
                        section[image->num_sections].size = 0x0;
                        section[image->num_sections].flags = 0;
                        section[image->num_sections].private =
                            &ihex->buffer[cooked_bytes];
                    }
                    section[image->num_sections].base_address =
                        (full_address & 0xffff) | (upper_address << 4);
                    full_address = (full_address & 0xffff) | (upper_address << 4);
                }
            } else if (record_type == 3) {  /* Start Segment Address Record */
                uint32_t dummy;
 
                /* "Start Segment Address Record" will not be supported
                 * but we must consume it, and do not create an error.  */
                while (count-- > 0) {
                    sscanf(&lpsz_line[bytes_read], "%2" SCNx32, &dummy);
                    cal_checksum += (uint8_t)dummy;
                    bytes_read += 2;
                }
            } else if (record_type == 4) {  /* Extended Linear Address Record */
                uint16_t upper_address;
 
                sscanf(&lpsz_line[bytes_read], "%4hx", &upper_address);
                cal_checksum += (uint8_t)(upper_address >> 8);
                cal_checksum += (uint8_t)upper_address;
                bytes_read += 4;
 
                if ((full_address >> 16) != upper_address) {
                    /* we encountered a nonconsecutive location, create a new section,
                     * unless the current section has zero size, in which case this specifies
                     * the current section's base address
                     */
                    if (section[image->num_sections].size != 0) {
                        image->num_sections++;
                        if (image->num_sections >= IMAGE_MAX_SECTIONS) {
                            /* too many sections */
                            LOG_ERROR("Too many sections found in IHEX file");
                            return ERROR_IMAGE_FORMAT_ERROR;
                        }
                        section[image->num_sections].size = 0x0;
                        section[image->num_sections].flags = 0;
                        section[image->num_sections].private =
                            &ihex->buffer[cooked_bytes];
                    }
                    section[image->num_sections].base_address =
                        (full_address & 0xffff) | (upper_address << 16);
                    full_address = (full_address & 0xffff) | (upper_address << 16);
                }
            } else if (record_type == 5) {  /* Start Linear Address Record */
                uint32_t start_address;
 
                sscanf(&lpsz_line[bytes_read], "%8" SCNx32, &start_address);
                cal_checksum += (uint8_t)(start_address >> 24);
                cal_checksum += (uint8_t)(start_address >> 16);
                cal_checksum += (uint8_t)(start_address >> 8);
                cal_checksum += (uint8_t)start_address;
                bytes_read += 8;
 
                image->start_address_set = true;
                image->start_address = be_to_h_u32((uint8_t *)&start_address);
            } else {
                LOG_ERROR("unhandled IHEX record type: %i", (int)record_type);
                return ERROR_IMAGE_FORMAT_ERROR;
            }
 
            sscanf(&lpsz_line[bytes_read], "%2" SCNx32, &checksum);
 
            if ((uint8_t)checksum != (uint8_t)(~cal_checksum + 1)) {
                /* checksum failed */
                LOG_ERROR("incorrect record checksum found in IHEX file");
                return ERROR_IMAGE_CHECKSUM;
            }
 
            if (end_rec) {
                end_rec = false;
                LOG_WARNING("continuing after end-of-file record: %.40s", lpsz_line);
            }
        }
    }
 
    if (end_rec)
        return ERROR_OK;
    else {
        LOG_ERROR("premature end of IHEX file, no matching end-of-file record found");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
}
 
static int image_ihex_buffer_complete(struct image *image)
{
    char *lpsz_line = malloc(1023);
    if (!lpsz_line) {
        LOG_ERROR("Out of memory");
        return ERROR_FAIL;
    }
    struct imagesection *section = malloc(sizeof(struct imagesection) * IMAGE_MAX_SECTIONS);
    if (!section) {
        free(lpsz_line);
        LOG_ERROR("Out of memory");
        return ERROR_FAIL;
    }
    int retval;
 
    retval = image_ihex_buffer_complete_inner(image, lpsz_line, section);
 
    free(section);
    free(lpsz_line);
 
    return retval;
}
 
static int image_elf32_read_headers(struct image *image)
{
    struct image_elf *elf = image->type_private;
    size_t read_bytes;
    uint32_t i, j;
    int retval;
    uint32_t nload;
    bool load_to_vaddr = false;
 
    retval = fileio_seek(elf->fileio, 0);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot seek to ELF file header, read failed");
        return retval;
    }
 
    elf->header32 = malloc(sizeof(Elf32_Ehdr));
 
    if (!elf->header32) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    retval = fileio_read(elf->fileio, sizeof(Elf32_Ehdr), (uint8_t *)elf->header32, &read_bytes);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot read ELF file header, read failed");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
    if (read_bytes != sizeof(Elf32_Ehdr)) {
        LOG_ERROR("cannot read ELF file header, only partially read");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    elf->segment_count = field16(elf, elf->header32->e_phnum);
    if (elf->segment_count == 0) {
        LOG_ERROR("invalid ELF file, no program headers");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    retval = fileio_seek(elf->fileio, field32(elf, elf->header32->e_phoff));
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot seek to ELF program header table, read failed");
        return retval;
    }
 
    elf->segments32 = malloc(elf->segment_count*sizeof(Elf32_Phdr));
    if (!elf->segments32) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    retval = fileio_read(elf->fileio, elf->segment_count*sizeof(Elf32_Phdr),
            (uint8_t *)elf->segments32, &read_bytes);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot read ELF segment headers, read failed");
        return retval;
    }
    if (read_bytes != elf->segment_count*sizeof(Elf32_Phdr)) {
        LOG_ERROR("cannot read ELF segment headers, only partially read");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    /* count useful segments (loadable), ignore BSS section */
    image->num_sections = 0;
    for (i = 0; i < elf->segment_count; i++)
        if ((field32(elf,
            elf->segments32[i].p_type) == PT_LOAD) &&
            (field32(elf, elf->segments32[i].p_filesz) != 0))
            image->num_sections++;
 
    if (image->num_sections == 0) {
        LOG_ERROR("invalid ELF file, no loadable segments");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    for (nload = 0, i = 0; i < elf->segment_count; i++)
        if (elf->segments32[i].p_paddr != 0)
            break;
        else if ((field32(elf,
            elf->segments32[i].p_type) == PT_LOAD) &&
            (field32(elf, elf->segments32[i].p_memsz) != 0))
            ++nload;
 
    if (i >= elf->segment_count && nload > 1)
        load_to_vaddr = true;
 
    /* alloc and fill sections array with loadable segments */
    image->sections = malloc(image->num_sections * sizeof(struct imagesection));
    if (!image->sections) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    for (i = 0, j = 0; i < elf->segment_count; i++) {
        if ((field32(elf,
            elf->segments32[i].p_type) == PT_LOAD) &&
            (field32(elf, elf->segments32[i].p_filesz) != 0)) {
            image->sections[j].size = field32(elf, elf->segments32[i].p_filesz);
            if (load_to_vaddr)
                image->sections[j].base_address = field32(elf,
                        elf->segments32[i].p_vaddr);
            else
                image->sections[j].base_address = field32(elf,
                        elf->segments32[i].p_paddr);
            image->sections[j].private = &elf->segments32[i];
            image->sections[j].flags = field32(elf, elf->segments32[i].p_flags);
            j++;
        }
    }
 
    image->start_address_set = true;
    image->start_address = field32(elf, elf->header32->e_entry);
 
    return ERROR_OK;
}
 
static int image_elf64_read_headers(struct image *image)
{
    struct image_elf *elf = image->type_private;
    size_t read_bytes;
    uint32_t i, j;
    int retval;
    uint32_t nload;
    bool load_to_vaddr = false;
 
    retval = fileio_seek(elf->fileio, 0);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot seek to ELF file header, read failed");
        return retval;
    }
 
    elf->header64 = malloc(sizeof(Elf64_Ehdr));
 
    if (!elf->header64) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    retval = fileio_read(elf->fileio, sizeof(Elf64_Ehdr), (uint8_t *)elf->header64, &read_bytes);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot read ELF file header, read failed");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
    if (read_bytes != sizeof(Elf64_Ehdr)) {
        LOG_ERROR("cannot read ELF file header, only partially read");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    elf->segment_count = field16(elf, elf->header64->e_phnum);
    if (elf->segment_count == 0) {
        LOG_ERROR("invalid ELF file, no program headers");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    retval = fileio_seek(elf->fileio, field64(elf, elf->header64->e_phoff));
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot seek to ELF program header table, read failed");
        return retval;
    }
 
    elf->segments64 = malloc(elf->segment_count*sizeof(Elf64_Phdr));
    if (!elf->segments64) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    retval = fileio_read(elf->fileio, elf->segment_count*sizeof(Elf64_Phdr),
            (uint8_t *)elf->segments64, &read_bytes);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot read ELF segment headers, read failed");
        return retval;
    }
    if (read_bytes != elf->segment_count*sizeof(Elf64_Phdr)) {
        LOG_ERROR("cannot read ELF segment headers, only partially read");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    /* count useful segments (loadable), ignore BSS section */
    image->num_sections = 0;
    for (i = 0; i < elf->segment_count; i++)
        if ((field32(elf,
            elf->segments64[i].p_type) == PT_LOAD) &&
            (field64(elf, elf->segments64[i].p_filesz) != 0))
            image->num_sections++;
 
    if (image->num_sections == 0) {
        LOG_ERROR("invalid ELF file, no loadable segments");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    for (nload = 0, i = 0; i < elf->segment_count; i++)
        if (elf->segments64[i].p_paddr != 0)
            break;
        else if ((field32(elf,
            elf->segments64[i].p_type) == PT_LOAD) &&
            (field64(elf, elf->segments64[i].p_memsz) != 0))
            ++nload;
 
    if (i >= elf->segment_count && nload > 1)
        load_to_vaddr = true;
 
    /* alloc and fill sections array with loadable segments */
    image->sections = malloc(image->num_sections * sizeof(struct imagesection));
    if (!image->sections) {
        LOG_ERROR("insufficient memory to perform operation");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    for (i = 0, j = 0; i < elf->segment_count; i++) {
        if ((field32(elf,
            elf->segments64[i].p_type) == PT_LOAD) &&
            (field64(elf, elf->segments64[i].p_filesz) != 0)) {
            image->sections[j].size = field64(elf, elf->segments64[i].p_filesz);
            if (load_to_vaddr)
                image->sections[j].base_address = field64(elf,
                        elf->segments64[i].p_vaddr);
            else
                image->sections[j].base_address = field64(elf,
                        elf->segments64[i].p_paddr);
            image->sections[j].private = &elf->segments64[i];
            image->sections[j].flags = field64(elf, elf->segments64[i].p_flags);
            j++;
        }
    }
 
    image->start_address_set = true;
    image->start_address = field64(elf, elf->header64->e_entry);
 
    return ERROR_OK;
}
 
static int image_elf_read_headers(struct image *image)
{
    struct image_elf *elf = image->type_private;
    size_t read_bytes;
    unsigned char e_ident[EI_NIDENT];
    int retval;
 
    retval = fileio_read(elf->fileio, EI_NIDENT, e_ident, &read_bytes);
    if (retval != ERROR_OK) {
        LOG_ERROR("cannot read ELF file header, read failed");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
    if (read_bytes != EI_NIDENT) {
        LOG_ERROR("cannot read ELF file header, only partially read");
        return ERROR_FILEIO_OPERATION_FAILED;
    }
 
    if (strncmp((char *)e_ident, ELFMAG, SELFMAG) != 0) {
        LOG_ERROR("invalid ELF file, bad magic number");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    elf->endianness = e_ident[EI_DATA];
    if ((elf->endianness != ELFDATA2LSB)
        && (elf->endianness != ELFDATA2MSB)) {
        LOG_ERROR("invalid ELF file, unknown endianness setting");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
 
    switch (e_ident[EI_CLASS]) {
    case ELFCLASS32:
        LOG_DEBUG("ELF32 image detected.");
        elf->is_64_bit = false;
        return image_elf32_read_headers(image);
 
    case ELFCLASS64:
        LOG_DEBUG("ELF64 image detected.");
        elf->is_64_bit = true;
        return image_elf64_read_headers(image);
 
    default:
        LOG_ERROR("invalid ELF file, only 32/64 bit ELF files are supported");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
}
 
static int image_elf32_read_section(struct image *image,
    int section,
    target_addr_t offset,
    uint32_t size,
    uint8_t *buffer,
    size_t *size_read)
{
    struct image_elf *elf = image->type_private;
    Elf32_Phdr *segment = (Elf32_Phdr *)image->sections[section].private;
    size_t read_size, really_read;
    int retval;
 
    *size_read = 0;
 
    LOG_DEBUG("load segment %d at 0x%" TARGET_PRIxADDR " (sz = 0x%" PRIx32 ")", section, offset, size);
 
    /* read initialized data in current segment if any */
    if (offset < field32(elf, segment->p_filesz)) {
        /* maximal size present in file for the current segment */
        read_size = MIN(size, field32(elf, segment->p_filesz) - offset);
        LOG_DEBUG("read elf: size = 0x%zx at 0x%" TARGET_PRIxADDR "", read_size,
            field32(elf, segment->p_offset) + offset);
        /* read initialized area of the segment */
        retval = fileio_seek(elf->fileio, field32(elf, segment->p_offset) + offset);
        if (retval != ERROR_OK) {
            LOG_ERROR("cannot find ELF segment content, seek failed");
            return retval;
        }
        retval = fileio_read(elf->fileio, read_size, buffer, &really_read);
        if (retval != ERROR_OK) {
            LOG_ERROR("cannot read ELF segment content, read failed");
            return retval;
        }
        size -= read_size;
        *size_read += read_size;
        /* need more data ? */
        if (!size)
            return ERROR_OK;
    }
 
    return ERROR_OK;
}
 
static int image_elf64_read_section(struct image *image,
    int section,
    target_addr_t offset,
    uint32_t size,
    uint8_t *buffer,
    size_t *size_read)
{
    struct image_elf *elf = image->type_private;
    Elf64_Phdr *segment = (Elf64_Phdr *)image->sections[section].private;
    size_t read_size, really_read;
    int retval;
 
    *size_read = 0;
 
    LOG_DEBUG("load segment %d at 0x%" TARGET_PRIxADDR " (sz = 0x%" PRIx32 ")", section, offset, size);
 
    /* read initialized data in current segment if any */
    if (offset < field64(elf, segment->p_filesz)) {
        /* maximal size present in file for the current segment */
        read_size = MIN(size, field64(elf, segment->p_filesz) - offset);
        LOG_DEBUG("read elf: size = 0x%zx at 0x%" TARGET_PRIxADDR "", read_size,
            field64(elf, segment->p_offset) + offset);
        /* read initialized area of the segment */
        retval = fileio_seek(elf->fileio, field64(elf, segment->p_offset) + offset);
        if (retval != ERROR_OK) {
            LOG_ERROR("cannot find ELF segment content, seek failed");
            return retval;
        }
        retval = fileio_read(elf->fileio, read_size, buffer, &really_read);
        if (retval != ERROR_OK) {
            LOG_ERROR("cannot read ELF segment content, read failed");
            return retval;
        }
        size -= read_size;
        *size_read += read_size;
        /* need more data ? */
        if (!size)
            return ERROR_OK;
    }
 
    return ERROR_OK;
}
 
static int image_elf_read_section(struct image *image,
    int section,
    target_addr_t offset,
    uint32_t size,
    uint8_t *buffer,
    size_t *size_read)
{
    struct image_elf *elf = image->type_private;
 
    if (elf->is_64_bit)
        return image_elf64_read_section(image, section, offset, size, buffer, size_read);
    else
        return image_elf32_read_section(image, section, offset, size, buffer, size_read);
}
 
static int image_mot_buffer_complete_inner(struct image *image,
    char *lpsz_line,
    struct imagesection *section)
{
    struct image_mot *mot = image->type_private;
    struct fileio *fileio = mot->fileio;
    uint32_t full_address;
    uint32_t cooked_bytes;
    bool end_rec = false;
 
    /* we can't determine the number of sections that we'll have to create ahead of time,
     * so we locally hold them until parsing is finished */
 
    int retval;
    size_t filesize;
    retval = fileio_size(fileio, &filesize);
    if (retval != ERROR_OK)
        return retval;
 
    mot->buffer = malloc(filesize >> 1);
    cooked_bytes = 0x0;
    image->num_sections = 0;
 
    while (!fileio_feof(fileio)) {
        full_address = 0x0;
        section[image->num_sections].private = &mot->buffer[cooked_bytes];
        section[image->num_sections].base_address = 0x0;
        section[image->num_sections].size = 0x0;
        section[image->num_sections].flags = 0;
 
        while (fileio_fgets(fileio, 1023, lpsz_line) == ERROR_OK) {
            uint32_t count;
            uint32_t address;
            uint32_t record_type;
            uint32_t checksum;
            uint8_t cal_checksum = 0;
            uint32_t bytes_read = 0;
 
            /* skip comments and blank lines */
            if ((lpsz_line[0] == '#') || (strlen(lpsz_line + strspn(lpsz_line, "\n\t\r ")) == 0))
                continue;
 
            /* get record type and record length */
            if (sscanf(&lpsz_line[bytes_read], "S%1" SCNx32 "%2" SCNx32, &record_type,
                &count) != 2)
                return ERROR_IMAGE_FORMAT_ERROR;
 
            bytes_read += 4;
            cal_checksum += (uint8_t)count;
 
            /* skip checksum byte */
            count -= 1;
 
            if (record_type == 0) {
                /* S0 - starting record (optional) */
                int value;
 
                while (count-- > 0) {
                    sscanf(&lpsz_line[bytes_read], "%2x", &value);
                    cal_checksum += (uint8_t)value;
                    bytes_read += 2;
                }
            } else if (record_type >= 1 && record_type <= 3) {
                switch (record_type) {
                    case 1:
                        /* S1 - 16 bit address data record */
                        sscanf(&lpsz_line[bytes_read], "%4" SCNx32, &address);
                        cal_checksum += (uint8_t)(address >> 8);
                        cal_checksum += (uint8_t)address;
                        bytes_read += 4;
                        count -= 2;
                        break;
 
                    case 2:
                        /* S2 - 24 bit address data record */
                        sscanf(&lpsz_line[bytes_read], "%6" SCNx32, &address);
                        cal_checksum += (uint8_t)(address >> 16);
                        cal_checksum += (uint8_t)(address >> 8);
                        cal_checksum += (uint8_t)address;
                        bytes_read += 6;
                        count -= 3;
                        break;
 
                    case 3:
                        /* S3 - 32 bit address data record */
                        sscanf(&lpsz_line[bytes_read], "%8" SCNx32, &address);
                        cal_checksum += (uint8_t)(address >> 24);
                        cal_checksum += (uint8_t)(address >> 16);
                        cal_checksum += (uint8_t)(address >> 8);
                        cal_checksum += (uint8_t)address;
                        bytes_read += 8;
                        count -= 4;
                        break;
 
                }
 
                if (full_address != address) {
                    /* we encountered a nonconsecutive location, create a new section,
                     * unless the current section has zero size, in which case this specifies
                     * the current section's base address
                     */
                    if (section[image->num_sections].size != 0) {
                        image->num_sections++;
                        section[image->num_sections].size = 0x0;
                        section[image->num_sections].flags = 0;
                        section[image->num_sections].private =
                            &mot->buffer[cooked_bytes];
                    }
                    section[image->num_sections].base_address = address;
                    full_address = address;
                }
 
                while (count-- > 0) {
                    unsigned value;
                    sscanf(&lpsz_line[bytes_read], "%2x", &value);
                    mot->buffer[cooked_bytes] = (uint8_t)value;
                    cal_checksum += (uint8_t)mot->buffer[cooked_bytes];
                    bytes_read += 2;
                    cooked_bytes += 1;
                    section[image->num_sections].size += 1;
                    full_address++;
                }
            } else if (record_type == 5 || record_type == 6) {
                /* S5 and S6 are the data count records, we ignore them */
                uint32_t dummy;
 
                while (count-- > 0) {
                    sscanf(&lpsz_line[bytes_read], "%2" SCNx32, &dummy);
                    cal_checksum += (uint8_t)dummy;
                    bytes_read += 2;
                }
            } else if (record_type >= 7 && record_type <= 9) {
                /* S7, S8, S9 - ending records for 32, 24 and 16bit */
                image->num_sections++;
 
                /* copy section information */
                image->sections = malloc(sizeof(struct imagesection) * image->num_sections);
                for (unsigned int i = 0; i < image->num_sections; i++) {
                    image->sections[i].private = section[i].private;
                    image->sections[i].base_address = section[i].base_address;
                    image->sections[i].size = section[i].size;
                    image->sections[i].flags = section[i].flags;
                }
 
                end_rec = true;
                break;
            } else {
                LOG_ERROR("unhandled S19 record type: %i", (int)(record_type));
                return ERROR_IMAGE_FORMAT_ERROR;
            }
 
            /* account for checksum, will always be 0xFF */
            sscanf(&lpsz_line[bytes_read], "%2" SCNx32, &checksum);
            cal_checksum += (uint8_t)checksum;
 
            if (cal_checksum != 0xFF) {
                /* checksum failed */
                LOG_ERROR("incorrect record checksum found in S19 file");
                return ERROR_IMAGE_CHECKSUM;
            }
 
            if (end_rec) {
                end_rec = false;
                LOG_WARNING("continuing after end-of-file record: %.40s", lpsz_line);
            }
        }
    }
 
    if (end_rec)
        return ERROR_OK;
    else {
        LOG_ERROR("premature end of S19 file, no matching end-of-file record found");
        return ERROR_IMAGE_FORMAT_ERROR;
    }
}
 
static int image_mot_buffer_complete(struct image *image)
{
    char *lpsz_line = malloc(1023);
    if (!lpsz_line) {
        LOG_ERROR("Out of memory");
        return ERROR_FAIL;
    }
    struct imagesection *section = malloc(sizeof(struct imagesection) * IMAGE_MAX_SECTIONS);
    if (!section) {
        free(lpsz_line);
        LOG_ERROR("Out of memory");
        return ERROR_FAIL;
    }
    int retval;
 
    retval = image_mot_buffer_complete_inner(image, lpsz_line, section);
 
    free(section);
    free(lpsz_line);
 
    return retval;
}
 
int image_open(struct image *image, const char *url, const char *type_string)
{
    int retval = ERROR_OK;
 
    retval = identify_image_type(image, type_string, url);
    if (retval != ERROR_OK)
        return retval;
 
    if (image->type == IMAGE_BINARY) {
        struct image_binary *image_binary;
 
        image_binary = image->type_private = malloc(sizeof(struct image_binary));
 
        retval = fileio_open(&image_binary->fileio, url, FILEIO_READ, FILEIO_BINARY);
        if (retval != ERROR_OK)
            return retval;
        size_t filesize;
        retval = fileio_size(image_binary->fileio, &filesize);
        if (retval != ERROR_OK) {
            fileio_close(image_binary->fileio);
            return retval;
        }
 
        image->num_sections = 1;
        image->sections = malloc(sizeof(struct imagesection));
        image->sections[0].base_address = 0x0;
        image->sections[0].size = filesize;
        image->sections[0].flags = 0;
    } else if (image->type == IMAGE_IHEX) {
        struct image_ihex *image_ihex;
 
        image_ihex = image->type_private = malloc(sizeof(struct image_ihex));
 
        retval = fileio_open(&image_ihex->fileio, url, FILEIO_READ, FILEIO_TEXT);
        if (retval != ERROR_OK)
            return retval;
 
        retval = image_ihex_buffer_complete(image);
        if (retval != ERROR_OK) {
            LOG_ERROR(
                "failed buffering IHEX image, check server output for additional information");
            fileio_close(image_ihex->fileio);
            return retval;
        }
    } else if (image->type == IMAGE_ELF) {
        struct image_elf *image_elf;
 
        image_elf = image->type_private = malloc(sizeof(struct image_elf));
 
        retval = fileio_open(&image_elf->fileio, url, FILEIO_READ, FILEIO_BINARY);
        if (retval != ERROR_OK)
            return retval;
 
        retval = image_elf_read_headers(image);
        if (retval != ERROR_OK) {
            fileio_close(image_elf->fileio);
            return retval;
        }
    } else if (image->type == IMAGE_MEMORY) {
        struct target *target = get_target(url);
 
        if (!target) {
            LOG_ERROR("target '%s' not defined", url);
            return ERROR_FAIL;
        }
 
        struct image_memory *image_memory;
 
        image->num_sections = 1;
        image->sections = malloc(sizeof(struct imagesection));
        image->sections[0].base_address = 0x0;
        image->sections[0].size = 0xffffffff;
        image->sections[0].flags = 0;
 
        image_memory = image->type_private = malloc(sizeof(struct image_memory));
 
        image_memory->target = target;
        image_memory->cache = NULL;
        image_memory->cache_address = 0x0;
    } else if (image->type == IMAGE_SRECORD) {
        struct image_mot *image_mot;
 
        image_mot = image->type_private = malloc(sizeof(struct image_mot));
 
        retval = fileio_open(&image_mot->fileio, url, FILEIO_READ, FILEIO_TEXT);
        if (retval != ERROR_OK)
            return retval;
 
        retval = image_mot_buffer_complete(image);
        if (retval != ERROR_OK) {
            LOG_ERROR(
                "failed buffering S19 image, check server output for additional information");
            fileio_close(image_mot->fileio);
            return retval;
        }
    } else if (image->type == IMAGE_BUILDER) {
        image->num_sections = 0;
        image->base_address_set = false;
        image->sections = NULL;
        image->type_private = NULL;
    }
 
    if (image->base_address_set) {
        /* relocate */
        for (unsigned int section = 0; section < image->num_sections; section++)
            image->sections[section].base_address += image->base_address;
                                            /* we're done relocating. The two statements below are mainly
                                            * for documentation purposes: stop anyone from empirically
                                            * thinking they should use these values henceforth. */
        image->base_address = 0;
        image->base_address_set = false;
    }
 
    return retval;
};
 
int image_read_section(struct image *image,
    int section,
    target_addr_t offset,
    uint32_t size,
    uint8_t *buffer,
    size_t *size_read)
{
    int retval;
 
    /* don't read past the end of a section */
    if (offset + size > image->sections[section].size) {
        LOG_DEBUG(
            "read past end of section: 0x%8.8" TARGET_PRIxADDR " + 0x%8.8" PRIx32 " > 0x%8.8" PRIx32 "",
            offset,
            size,
            image->sections[section].size);
        return ERROR_COMMAND_SYNTAX_ERROR;
    }
 
    if (image->type == IMAGE_BINARY) {
        struct image_binary *image_binary = image->type_private;
 
        /* only one section in a plain binary */
        if (section != 0)
            return ERROR_COMMAND_SYNTAX_ERROR;
 
        /* seek to offset */
        retval = fileio_seek(image_binary->fileio, offset);
        if (retval != ERROR_OK)
            return retval;
 
        /* return requested bytes */
        retval = fileio_read(image_binary->fileio, size, buffer, size_read);
        if (retval != ERROR_OK)
            return retval;
    } else if (image->type == IMAGE_IHEX) {
        memcpy(buffer, (uint8_t *)image->sections[section].private + offset, size);
        *size_read = size;
 
        return ERROR_OK;
    } else if (image->type == IMAGE_ELF) {
        return image_elf_read_section(image, section, offset, size, buffer, size_read);
    } else if (image->type == IMAGE_MEMORY) {
        struct image_memory *image_memory = image->type_private;
        uint32_t address = image->sections[section].base_address + offset;
 
        *size_read = 0;
 
        while ((size - *size_read) > 0) {
            uint32_t size_in_cache;
 
            if (!image_memory->cache
                || (address < image_memory->cache_address)
                || (address >=
                (image_memory->cache_address + IMAGE_MEMORY_CACHE_SIZE))) {
                if (!image_memory->cache)
                    image_memory->cache = malloc(IMAGE_MEMORY_CACHE_SIZE);
 
                if (target_read_buffer(image_memory->target, address &
                    ~(IMAGE_MEMORY_CACHE_SIZE - 1),
                    IMAGE_MEMORY_CACHE_SIZE, image_memory->cache) != ERROR_OK) {
                    free(image_memory->cache);
                    image_memory->cache = NULL;
                    return ERROR_IMAGE_TEMPORARILY_UNAVAILABLE;
                }
                image_memory->cache_address = address &
                    ~(IMAGE_MEMORY_CACHE_SIZE - 1);
            }
 
            size_in_cache =
                (image_memory->cache_address + IMAGE_MEMORY_CACHE_SIZE) - address;
 
            memcpy(buffer + *size_read,
                image_memory->cache + (address - image_memory->cache_address),
                (size_in_cache > size) ? size : size_in_cache
                );
 
            *size_read += (size_in_cache > size) ? size : size_in_cache;
            address += (size_in_cache > size) ? size : size_in_cache;
        }
    } else if (image->type == IMAGE_SRECORD) {
        memcpy(buffer, (uint8_t *)image->sections[section].private + offset, size);
        *size_read = size;
 
        return ERROR_OK;
    } else if (image->type == IMAGE_BUILDER) {
        memcpy(buffer, (uint8_t *)image->sections[section].private + offset, size);
        *size_read = size;
 
        return ERROR_OK;
    }
 
    return ERROR_OK;
}
 
int image_add_section(struct image *image, target_addr_t base, uint32_t size, uint64_t flags, uint8_t const *data)
{
    struct imagesection *section;
 
    /* only image builder supports adding sections */
    if (image->type != IMAGE_BUILDER)
        return ERROR_COMMAND_SYNTAX_ERROR;
 
    /* see if there's a previous section */
    if (image->num_sections) {
        section = &image->sections[image->num_sections - 1];
 
        /* see if it's enough to extend the last section,
         * adding data to previous sections or merging is not supported */
        if (((section->base_address + section->size) == base) &&
            (section->flags == flags)) {
            section->private = realloc(section->private, section->size + size);
            memcpy((uint8_t *)section->private + section->size, data, size);
            section->size += size;
            return ERROR_OK;
        }
    }
 
    /* allocate new section */
    image->num_sections++;
    image->sections =
        realloc(image->sections, sizeof(struct imagesection) * image->num_sections);
    section = &image->sections[image->num_sections - 1];
    section->base_address = base;
    section->size = size;
    section->flags = flags;
    section->private = malloc(sizeof(uint8_t) * size);
    memcpy((uint8_t *)section->private, data, size);
 
    return ERROR_OK;
}
 
void image_close(struct image *image)
{
    if (image->type == IMAGE_BINARY) {
        struct image_binary *image_binary = image->type_private;
 
        fileio_close(image_binary->fileio);
    } else if (image->type == IMAGE_IHEX) {
        struct image_ihex *image_ihex = image->type_private;
 
        fileio_close(image_ihex->fileio);
 
        free(image_ihex->buffer);
        image_ihex->buffer = NULL;
    } else if (image->type == IMAGE_ELF) {
        struct image_elf *image_elf = image->type_private;
 
        fileio_close(image_elf->fileio);
 
        if (image_elf->is_64_bit) {
            free(image_elf->header64);
            image_elf->header64 = NULL;
 
            free(image_elf->segments64);
            image_elf->segments64 = NULL;
        } else {
            free(image_elf->header32);
            image_elf->header32 = NULL;
 
            free(image_elf->segments32);
            image_elf->segments32 = NULL;
        }
    } else if (image->type == IMAGE_MEMORY) {
        struct image_memory *image_memory = image->type_private;
 
        free(image_memory->cache);
        image_memory->cache = NULL;
    } else if (image->type == IMAGE_SRECORD) {
        struct image_mot *image_mot = image->type_private;
 
        fileio_close(image_mot->fileio);
 
        free(image_mot->buffer);
        image_mot->buffer = NULL;
    } else if (image->type == IMAGE_BUILDER) {
        for (unsigned int i = 0; i < image->num_sections; i++) {
            free(image->sections[i].private);
            image->sections[i].private = NULL;
        }
    }
 
    free(image->type_private);
    image->type_private = NULL;
 
    free(image->sections);
    image->sections = NULL;
}
 
int image_calculate_checksum(const uint8_t *buffer, uint32_t nbytes, uint32_t *checksum)
{
    uint32_t crc = 0xffffffff;
    LOG_DEBUG("Calculating checksum");
 
    static uint32_t crc32_table[256];
 
    static bool first_init;
    if (!first_init) {
        /* Initialize the CRC table and the decoding table.  */
        unsigned int i, j, c;
        for (i = 0; i < 256; i++) {
            /* as per gdb */
            for (c = i << 24, j = 8; j > 0; --j)
                c = c & 0x80000000 ? (c << 1) ^ 0x04c11db7 : (c << 1);
            crc32_table[i] = c;
        }
 
        first_init = true;
    }
 
    while (nbytes > 0) {
        int run = nbytes;
        if (run > 32768)
            run = 32768;
        nbytes -= run;
        while (run--) {
            /* as per gdb */
            crc = (crc << 8) ^ crc32_table[((crc >> 24) ^ *buffer++) & 255];
        }
        keep_alive();
    }
 
    LOG_DEBUG("Calculating checksum done; checksum=0x%" PRIx32, crc);
 
    *checksum = crc;
    return ERROR_OK;
}