program.c

/*
 * Copyright (c) 2016-2017, Linaro Ltd.
 * All rights reserved.
 *
 * 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 of the copyright holder 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 HOLDER 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.
 */
#include <errno.h>
#include <fcntl.h>
#include <linux/limits.h>
#include <string.h>
#include <unistd.h>
#include <libxml/parser.h>
#include <libxml/tree.h>

#include "program.h"
#include "qdl.h"

static struct program *programs;
static struct program *programs_last;

static int load_erase_tag(xmlNode *node, bool is_nand) {
    struct program *program;
    int errors = 0;

    if (!is_nand) {
        fprintf(stderr, "got \"erase\" tag for non-NAND storage\n");
        return -EINVAL;
    }

    program = calloc(1, sizeof(struct program));


    program->is_nand = true;
    program->is_erase = true;

    program->pages_per_block = attr_as_unsigned(node, "PAGES_PER_BLOCK", &errors);
    program->sector_size = attr_as_unsigned(node, "SECTOR_SIZE_IN_BYTES", &errors);
    program->num_sectors = attr_as_unsigned(node, "num_partition_sectors", &errors);
    program->start_sector = attr_as_string(node, "start_sector", &errors);

    if (errors) {
        fprintf(stderr, "[PROGRAM] errors while parsing erase tag\n");
        free(program);
        return -EINVAL;
    }

    if (programs) {
        programs_last->next = program;
        programs_last = program;
    } else {
        programs = program;
        programs_last = program;
    }

    return 0;
}

static int load_program_tag(xmlNode *node, bool is_nand) {
    struct program *program;
    int errors = 0;

    program = calloc(1, sizeof(struct program));

    program->is_nand = is_nand;

    program->sector_size = attr_as_unsigned(node, "SECTOR_SIZE_IN_BYTES", &errors);
    program->filename = attr_as_string(node, "filename", &errors);
    program->label = attr_as_string(node, "label", &errors);
    program->num_sectors = attr_as_unsigned(node, "num_partition_sectors", &errors);
    program->partition = attr_as_unsigned(node, "physical_partition_number", &errors);
    program->start_sector = attr_as_string(node, "start_sector", &errors);

    if (is_nand) {
        program->pages_per_block = attr_as_unsigned(node, "PAGES_PER_BLOCK", &errors);
        if (NULL != xmlGetProp(node, (xmlChar *) "last_sector")) {
            program->last_sector = attr_as_unsigned(node, "last_sector", &errors);
        }
    } else {
        program->file_offset = attr_as_unsigned(node, "file_sector_offset", &errors);
    }

    if (errors) {
        fprintf(stderr, "[PROGRAM] errors while parsing program\n");
        free(program);
        return -EINVAL;
    }

    if (programs) {
        programs_last->next = program;
        programs_last = program;
    } else {
        programs = program;
        programs_last = program;
    }

    return 0;
}

int program_load(const char *program_file, bool is_nand) {
    xmlNode *node;
    xmlNode *root;
    xmlDoc *doc;
    int errors;

    doc = xmlReadFile(program_file, NULL, 0);
    if (!doc) {
        fprintf(stderr, "[PROGRAM] failed to parse %s\n", program_file);
        return -EINVAL;
    }

    root = xmlDocGetRootElement(doc);
    for (node = root->children; node; node = node->next) {
        if (node->type != XML_ELEMENT_NODE)
            continue;

        errors = -EINVAL;

        if (!xmlStrcmp(node->name, (xmlChar *) "erase"))
            errors = load_erase_tag(node, is_nand);
        else if (!xmlStrcmp(node->name, (xmlChar *) "program"))
            errors = load_program_tag(node, is_nand);
        else
            fprintf(stderr, "[PROGRAM] unrecognized tag \"%s\", ignoring\n", node->name);

        if (errors)
            return errors;
    }

    xmlFreeDoc(doc);

    return 0;
}

int program_execute(struct qdl_device *ctx, int (*apply)(struct qdl_device *ctx, struct program *program, int fd),
                    const char *incdir) {
    struct program *program;
    const char *filename;
    char tmp[PATH_MAX];
    int ret;
    int fd;

    for (program = programs; program; program = program->next) {
        if (program->is_erase || !program->filename)
            continue;

        filename = program->filename;
        if (incdir) {
            snprintf(tmp, PATH_MAX, "%s/%s", incdir, filename);
            if (access(tmp, F_OK) != -1)
                filename = tmp;
        }

        fd = open(filename, O_RDONLY);

        if (fd < 0) {
            printf("Unable to open %s...ignoring\n", program->filename);
            continue;
        }

        ret = apply(ctx, program, fd);

        close(fd);
        if (ret)
            return ret;
    }

    return 0;
}

int erase_execute(struct qdl_device *ctx, int (*apply)(struct qdl_device *ctx, struct program *program)) {
    struct program *program;
    int ret;


    for (program = programs; program; program = program->next) {
        if (!program->is_erase)
            continue;

        ret = apply(ctx, program);
        if (ret)
            return ret;
    }

    return 0;
}

/**
 * program_find_bootable_partition() - find one bootable partition
 *
 * Returns partition number, or negative errno on failure.
 *
 * Scan program tags for a partition with the label "sbl1", "xbl" or "xbl_a"
 * and return the partition number for this. If more than one line matches
 * we're assuming our logic is flawed and return an error.
 */
int program_find_bootable_partition(void) {
    struct program *program;
    const char *label;
    int part = -ENOENT;

    for (program = programs; program; program = program->next) {
        label = program->label;
        if (!label)
            continue;

        if (!strcmp(label, "xbl") || !strcmp(label, "xbl_a") ||
            !strcmp(label, "sbl1")) {
            if (part != -ENOENT)
                return -EINVAL;

            part = (int) program->partition;
        }
    }

    return part;
}