messages.c

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/*
 * Copyright 2004 James Bursa <bursa@users.sourceforge.net>
 * Copyright 2006 Rob Kendrick <rjek@rjek.com>
 *
 * This file is part of NetSurf, http://www.netsurf-browser.org/
 *
 * NetSurf 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; version 2 of the License.
 *
 * NetSurf 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
/**
 * \file
 * Localised message support implementation.
 *
 * Native language messages are loaded from a file and stored hashed by key for
 * fast access.
 */
 
#include <stdlib.h>
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#include <zlib.h>
#include <stdarg.h>
 
#include "utils/log.h"
#include "utils/messages.h"
#include "utils/utils.h"
#include "utils/hashtable.h"
 
/** Messages are stored in a fixed-size hash table. */
#define HASH_SIZE 101
 
/**
 * The hash table used to store the standard Messages file for the old API
 */
static struct hash_table *messages_hash = NULL;
 
 
/**
 * Create a message context
 *
 * generate a message context populated with english fallbacks for
 *   some formatted messages.
 */
static struct hash_table *messages_create_ctx(int hash_size)
{
        struct hash_table *nctx;
        const struct {
                const char *key;
                const char *value;
        } fallback[] = {
                { "LoginDescription",
                  "The site %s is requesting your username and password. "
                  "The realm is \"%s\""},
                { "PrivacyDescription",
                  "A privacy error occurred while communicating with %s this "
                  "may be a site configuration error or an attempt to steal "
                  "private information (passwords, messages or credit cards)"},
                { "TimeoutDescription",
                  "A connection to %s could not be established. The site may "
                  "be temporarily unavailable or too busy to respond."},
                { "FetchErrorDescription",
                  "An error occurred when connecting to %s"},
                { NULL, NULL}
        };
        nctx = hash_create(hash_size);
 
        if (nctx != NULL) {
                int floop;
                for (floop = 0; fallback[floop].key != NULL; floop++) {
                        hash_add(nctx,
                                 fallback[floop].key,
                                 fallback[floop].value);
                }
        }
 
        return nctx;
}
 
/**
 * Free memory used by a messages hash.
 * The context will not be valid after this function returns.
 *
 * \param  ctx  context of messages file to free
 */
static void messages_destroy_ctx(struct hash_table *ctx)
{
        if (ctx == NULL)
                return;
 
        hash_destroy(ctx);
}
 
 
/**
 * Read keys and values from messages file.
 *
 * \param  path  pathname of messages file
 * \param  ctx   reference of hash table to merge with or NULL to create one.
 * \return NSERROR_OK on sucess and ctx updated or error code on faliure.
 */
static nserror messages_load_ctx(const char *path, struct hash_table **ctx)
{
        struct hash_table *nctx; /* new context */
        nserror res;
 
        if (*ctx != NULL) {
                /**
                 * \note The passed hash is not copied here so this
                 * updates in place.
                 */
                return hash_add_file(*ctx, path);
        }
 
        nctx = messages_create_ctx(HASH_SIZE);
        if (nctx == NULL) {
                NSLOG(netsurf, INFO,
                      "Unable to create hash table for messages file %s",
                      path);
                return NSERROR_NOMEM;
        }
 
        res = hash_add_file(nctx, path);
        if (res == NSERROR_OK) {
                *ctx = nctx;
        } else {
                hash_destroy(nctx);
        }
 
        return res;
}
 
 
/**
 * Fast lookup of a message by key.
 *
 * \param  key  key of message
 * \param  ctx  context of messages file to look up in
 * \return value of message, or key if not found
 */
static const char *
messages_get_ctx(const char *key, struct hash_table *ctx)
{
        const char *r = NULL;
 
        assert(key != NULL);
 
        /* allow attempts to retrieve messages before context is set up. */
        if (ctx != NULL) {
                r = hash_get(ctx, key);
        }
 
        /* If called with no context or unable to retrive a value
         * return the key.
         */
        if (r == NULL) {
                r = key;
        }
 
        return r;
}
 
 
/* exported interface documented in messages.h */
nserror messages_add_from_file(const char *path)
{
        if (path == NULL) {
                return NSERROR_BAD_PARAMETER;
        }
 
        NSLOG(netsurf, INFO, "Loading Messages from '%s'", path);
 
        return messages_load_ctx(path, &messages_hash);
}
 
 
/* exported interface documented in messages.h */
nserror messages_add_from_inline(const uint8_t *data, size_t size)
{
        /* ensure the hash table is initialised */
        if (messages_hash == NULL) {
                messages_hash = messages_create_ctx(HASH_SIZE);
        }
        if (messages_hash == NULL) {
                NSLOG(netsurf, INFO, "Unable to create hash table");
                return NSERROR_NOMEM;
        }
        return hash_add_inline(messages_hash, data, size);
}
 
 
/* exported interface documented in messages.h */
char *messages_get_buff(const char *key, ...)
{
        const char *msg_fmt;
        char *buff = NULL; /* formatted buffer to return */
        int buff_len = 0;
        va_list ap;
 
        assert(key != NULL);
 
        if (messages_hash == NULL) {
                return NULL;
        }
 
        msg_fmt = hash_get(messages_hash, key);
 
        if (msg_fmt == NULL) {
                return NULL;
        }
 
        va_start(ap, key);
        buff_len = vsnprintf(buff, buff_len, msg_fmt, ap);
        va_end(ap);
 
        buff = malloc(buff_len + 1);
 
        if (buff != NULL) {
                va_start(ap, key);
                vsnprintf(buff, buff_len + 1, msg_fmt, ap);
                va_end(ap);
        }
 
        return buff;
}
 
 
/* exported function documented in utils/messages.h */
const char *messages_get(const char *key)
{
        return messages_get_ctx(key, messages_hash);
}
 
 
/* exported function documented in utils/messages.h */
const char *messages_get_errorcode(nserror code)
{
        switch (code) {
        case NSERROR_OK:
                /* No error */
                return messages_get_ctx("OK", messages_hash);
 
        case NSERROR_NOMEM:
                /* Memory exhaustion */
                return messages_get_ctx("NoMemory", messages_hash);
 
        case NSERROR_NO_FETCH_HANDLER:
                /* No fetch handler for URL scheme */
                return messages_get_ctx("NoHandler", messages_hash);
 
        case NSERROR_NOT_FOUND:
                /* Requested item not found */
                return messages_get_ctx("NotFound", messages_hash);
 
        case NSERROR_NOT_DIRECTORY:
                /* Missing directory */
                return messages_get_ctx("NotDirectory", messages_hash);
 
        case NSERROR_SAVE_FAILED:
                /* Failed to save data */
                return messages_get_ctx("SaveFailed", messages_hash);
 
        case NSERROR_CLONE_FAILED:
                /* Failed to clone handle */
                return messages_get_ctx("CloneFailed", messages_hash);
 
        case NSERROR_INIT_FAILED:
                /* Initialisation failed */
                return messages_get_ctx("InitFailed", messages_hash);
 
        case NSERROR_BMP_ERROR:
                /* A BMP error occurred */
                return messages_get_ctx("BMPError", messages_hash);
 
        case NSERROR_GIF_ERROR:
                /* A GIF error occurred */
                return messages_get_ctx("GIFError", messages_hash);
 
        case NSERROR_ICO_ERROR:
                /* A ICO error occurred */
                return messages_get_ctx("ICOError", messages_hash);
 
        case NSERROR_PNG_ERROR:
                /* A PNG error occurred */
                return messages_get_ctx("PNGError", messages_hash);
 
        case NSERROR_SPRITE_ERROR:
                /* A RISC OS Sprite error occurred */
                return messages_get_ctx("SpriteError", messages_hash);
 
        case NSERROR_SVG_ERROR:
                /* A SVG error occurred */
                return messages_get_ctx("SVGError", messages_hash);
 
        case NSERROR_BAD_ENCODING:
                /* The character set is unknown */
                return messages_get_ctx("BadEncoding", messages_hash);
 
        case NSERROR_NEED_DATA:
                /* More data needed */
                return messages_get_ctx("NeedData", messages_hash);
 
        case NSERROR_ENCODING_CHANGE:
                /* The character set encoding change was unhandled */
                return messages_get_ctx("EncodingChanged", messages_hash);
 
        case NSERROR_BAD_PARAMETER:
                /* Bad Parameter */
                return messages_get_ctx("BadParameter", messages_hash);
 
        case NSERROR_INVALID:
                /* Invalid data */
                return messages_get_ctx("Invalid", messages_hash);
 
        case NSERROR_BOX_CONVERT:
                /* Box conversion failed */
                return messages_get_ctx("BoxConvert", messages_hash);
 
        case NSERROR_STOPPED:
                /* Content conversion stopped */
                return messages_get_ctx("Stopped", messages_hash);
 
        case NSERROR_DOM:
                /* DOM call returned error */
                return messages_get_ctx("ParsingFail", messages_hash);
 
        case NSERROR_CSS:
                /* CSS call returned error */
                return messages_get_ctx("CSSGeneric", messages_hash);
 
        case NSERROR_CSS_BASE:
                /* CSS base sheet failed */
                return messages_get_ctx("CSSBase", messages_hash);
 
        case NSERROR_BAD_URL:
                /* Bad URL */
                return messages_get_ctx("BadURL", messages_hash);
 
        case NSERROR_BAD_CONTENT:
                /* Bad Content */
                return messages_get_ctx("BadContent", messages_hash);
 
        case NSERROR_FRAME_DEPTH:
                /* Exceeded frame depth */
                return messages_get_ctx("FrameDepth", messages_hash);
 
        case NSERROR_PERMISSION:
                /* Permission error */
                return messages_get_ctx("PermissionError", messages_hash);
 
        case NSERROR_BAD_SIZE:
                /* Bad size */
                return messages_get_ctx("BadSize", messages_hash);
 
        case NSERROR_NOSPACE:
                /* Insufficient space */
                return messages_get_ctx("NoSpace", messages_hash);
 
        case NSERROR_NOT_IMPLEMENTED:
                /* Functionality is not implemented */
                return messages_get_ctx("NotImplemented", messages_hash);
 
        case NSERROR_UNKNOWN:
                /* Unknown error */
                return messages_get_ctx("Unknown", messages_hash);
 
        case NSERROR_BAD_AUTH:
                /* Authentication required */
                return messages_get_ctx("BadAuth", messages_hash);
 
        case NSERROR_BAD_REDIRECT:
                /* To many redirects */
                return messages_get_ctx("TooManyRedirects", messages_hash);
 
        case NSERROR_BAD_CERTS:
                /* Certificate chain verification failure */
                return messages_get_ctx("CertificateVerificationNeeded", messages_hash);
 
        case NSERROR_TIMEOUT:
                /* Operation timed out */
                return messages_get_ctx("Timeout", messages_hash);
        }
 
        /* The switch has no default, so the compiler should tell us when we
         * forget to add messages for new error codes.  As such, we should
         * never get here.
         */
        assert(0);
        return messages_get_ctx("Unknown", messages_hash);
}
 
/* exported function documented in utils/messages.h */
const char *messages_get_sslcode(ssl_cert_err code)
{
        switch (code) {
        case SSL_CERT_ERR_OK:
                /* Nothing wrong with this certificate */
                return messages_get_ctx("SSLCertErrOk", messages_hash);
 
        case SSL_CERT_ERR_UNKNOWN:
                /* Unknown error */
                return messages_get_ctx("SSLCertErrUnknown", messages_hash);
 
        case SSL_CERT_ERR_BAD_ISSUER:
                /* Bad issuer */
                return messages_get_ctx("SSLCertErrBadIssuer", messages_hash);
 
        case SSL_CERT_ERR_BAD_SIG:
                /* Bad signature on this certificate */
                return messages_get_ctx("SSLCertErrBadSig", messages_hash);
 
        case SSL_CERT_ERR_TOO_YOUNG:
                /* This certificate is not yet valid */
                return messages_get_ctx("SSLCertErrTooYoung", messages_hash);
 
        case SSL_CERT_ERR_TOO_OLD:
                /* This certificate is no longer valid */
                return messages_get_ctx("SSLCertErrTooOld", messages_hash);
 
        case SSL_CERT_ERR_SELF_SIGNED:
                /* This certificate is self signed */
                return messages_get_ctx("SSLCertErrSelfSigned", messages_hash);
 
        case SSL_CERT_ERR_CHAIN_SELF_SIGNED:
                /* This certificate chain is self signed */
                return messages_get_ctx("SSLCertErrChainSelfSigned", messages_hash);
 
        case SSL_CERT_ERR_REVOKED:
                /* This certificate has been revoked */
                return messages_get_ctx("SSLCertErrRevoked", messages_hash);
 
        case SSL_CERT_ERR_HOSTNAME_MISMATCH:
                /* Common name is invalid */
                return messages_get_ctx("SSLCertErrHostnameMismatch", messages_hash);
 
        case SSL_CERT_ERR_CERT_MISSING:
                /* Common name is invalid */
                return messages_get_ctx("SSLCertErrCertMissing", messages_hash);
 
        }
 
        /* The switch has no default, so the compiler should tell us when we
         * forget to add messages for new error codes.  As such, we should
         * never get here.
         */
        assert(0);
        return messages_get_ctx("Unknown", messages_hash);
}
 
/* exported function documented in utils/messages.h */
void messages_destroy(void)
{
        messages_destroy_ctx(messages_hash);
        messages_hash = NULL;
}