source: mainline/uspace/lib/bithenge/src/print.c@ 16bfcd3

/*
 * Copyright (c) 2012 Sean Bartell
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

/** @addtogroup bithenge
 * @{
 */
/**
 * @file
 * Write a tree as JSON or other text formats.
 * @todo Allow more control over the printing style, and handle printing in
 * limited space.
 */

#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <wchar.h>
#include <bithenge/blob.h>
#include <bithenge/print.h>
#include <bithenge/tree.h>
#include "common.h"

typedef struct {
        bithenge_print_type_t type;
        bool first;
        int depth;
        char *buffer;
        size_t buffer_size;
} state_t;

static void state_printf(state_t *state, const char *format, ...)
{
        va_list ap;
        va_start(ap, format);
        if (state->buffer) {
                int rc = vsnprintf(state->buffer, state->buffer_size, format,
                    ap);
                if (rc > 0 && (size_t)rc >= state->buffer_size)
                        rc = state->buffer_size - 1;
                if (rc > 0) {
                        state->buffer += rc;
                        state->buffer_size -= rc;
                }
        } else {
                vprintf(format, ap);
        }
        va_end(ap);
}

static int print_node(state_t *, bithenge_node_t *);

static void newline(state_t *state)
{
        state_printf(state, "\n");
        for (int i = 0; i < state->depth; i++) {
                state_printf(state, "    ");
        }
}

static void increase_depth(state_t *state)
{
        state->depth++;
}

static void decrease_depth(state_t *state)
{
        state->depth--;
}

static int print_internal_func(bithenge_node_t *key, bithenge_node_t *value, void *data)
{
        state_t *state = (state_t *)data;
        int rc = EOK;
        if (!state->first)
                state_printf(state, ",");
        newline(state);
        state->first = false;
        bool add_quotes = state->type == BITHENGE_PRINT_JSON
            && bithenge_node_type(key) != BITHENGE_NODE_STRING;
        if (add_quotes)
                state_printf(state, "\"");
        rc = print_node(state, key);
        if (rc != EOK)
                goto end;
        if (add_quotes)
                state_printf(state, "\"");
        state_printf(state, ": ");
        rc = print_node(state, value);
        if (rc != EOK)
                goto end;
end:
        bithenge_node_dec_ref(key);
        bithenge_node_dec_ref(value);
        return rc;
}

static int print_internal(state_t *state, bithenge_node_t *node)
{
        int rc;
        state_printf(state, "{");
        increase_depth(state);
        state->first = true;
        rc = bithenge_node_for_each(node, print_internal_func, state);
        if (rc != EOK)
                return rc;
        decrease_depth(state);
        if (!state->first)
                newline(state);
        state->first = false;
        state_printf(state, "}");
        return EOK;
}

static int print_boolean(state_t *state, bithenge_node_t *node)
{
        bool value = bithenge_boolean_node_value(node);
        switch (state->type) {
        case BITHENGE_PRINT_PYTHON:
                state_printf(state, value ? "True" : "False");
                break;
        case BITHENGE_PRINT_JSON:
                state_printf(state, value ? "true" : "false");
                break;
        }
        return EOK;
}

static int print_integer(state_t *state, bithenge_node_t *node)
{
        bithenge_int_t value = bithenge_integer_node_value(node);
        state_printf(state, "%" BITHENGE_PRId, value);
        return EOK;
}

static int print_string(state_t *state, bithenge_node_t *node)
{
        const char *value = bithenge_string_node_value(node);
        state_printf(state, "\"");
        for (string_iterator_t i = string_iterator(value); !string_iterator_done(&i); ) {
                wchar_t ch;
                int rc = string_iterator_next(&i, &ch);
                if (rc != EOK)
                        return rc;
                if (ch == '"' || ch == '\\') {
                        state_printf(state, "\\%lc", (wint_t) ch);
                } else if (ch <= 0x1f) {
                        state_printf(state, "\\u%04x", (unsigned int) ch);
                } else {
                        state_printf(state, "%lc", (wint_t) ch);
                }
        }
        state_printf(state, "\"");
        return EOK;
}

static int print_blob(state_t *state, bithenge_node_t *node)
{
        bithenge_blob_t *blob = bithenge_node_as_blob(node);
        aoff64_t pos = 0;
        uint8_t buffer[1024];
        aoff64_t size = sizeof(buffer);
        int rc;
        state_printf(state,
            state->type == BITHENGE_PRINT_PYTHON ? "b\"" : "\"");
        do {
                rc = bithenge_blob_read(blob, pos, (char *)buffer, &size);
                if (rc != EOK)
                        return rc;
                for (aoff64_t i = 0; i < size; i++)
                        state_printf(state, "\\x%02x",
                            (unsigned int)buffer[i]);
                pos += size;
        } while (size == sizeof(buffer));
        state_printf(state, "\"");
        return EOK;
}

static int print_node(state_t *state, bithenge_node_t *tree)
{
        switch (bithenge_node_type(tree)) {
        case BITHENGE_NODE_INTERNAL:
                return print_internal(state, tree);
        case BITHENGE_NODE_BOOLEAN:
                return print_boolean(state, tree);
        case BITHENGE_NODE_INTEGER:
                return print_integer(state, tree);
        case BITHENGE_NODE_STRING:
                return print_string(state, tree);
        case BITHENGE_NODE_BLOB:
                return print_blob(state, tree);
        }
        return ENOTSUP;
}

/** Print a tree as text to stdout.
 * @param type The format to use.
 * @param tree The root node of the tree to print.
 * @return EOK on success or an error code from errno.h. */
int bithenge_print_node(bithenge_print_type_t type, bithenge_node_t *tree)
{
        state_t state = {type, true, 0, NULL, 0};
        return print_node(&state, tree);
}

/** Print a tree as text into a buffer.
 * @param[in,out] str Holds a pointer to the buffer; changed to point to the
 * null character.
 * @param[in,out] size Holds the size of the buffer; changed to hold the
 * remaining size.
 * @param type The format to use.
 * @param tree The root node of the tree to print.
 * @return EOK on success or an error code from errno.h. */
int bithenge_print_node_to_string(char **str, size_t *size,
    bithenge_print_type_t type, bithenge_node_t *tree)
{
        state_t state = {type, true, 0, *str, *size};
        int rc = print_node(&state, tree);
        *str = state.buffer;
        *size = state.buffer_size;
        return rc;
}

/** @}
 */