gerb_file.c

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/*
 * gEDA - GNU Electronic Design Automation
 * This file is a part of gerbv.
 *
 *   Copyright (C) 2000-2002 Stefan Petersen (spe@stacken.kth.se)
 *
 * $Id$
 *
 * This program 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; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111 USA
 */
 
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
 
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
 
#include <sys/types.h>
#include <sys/stat.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#endif
#include <errno.h>
#include <glib/gstdio.h>
 
#include "common.h"
#include "gerbv.h"
#include "gerb_file.h"
 
/* DEBUG printing.  #define DEBUG 1 in config.h to use this fcn. */
#define dprintf \
    if (DEBUG)  \
    printf
 
gerb_file_t*
gerb_fopen(const char* filename) {
    gerb_file_t* fd;
    struct stat  statinfo;
 
    dprintf("---> Entering gerb_fopen, filename = %s\n", filename);
 
    fd = g_new(gerb_file_t, 1);
    if (fd == NULL) {
        return NULL;
    }
 
    dprintf("     Doing fopen\n");
    /* fopen() can't open files with non ASCII filenames on windows */
    fd->fd = g_fopen(filename, "rb");
    if (fd->fd == NULL) {
        g_free(fd);
        return NULL;
    }
 
    dprintf("     Doing fstat\n");
    fd->ptr    = 0;
    fd->fileno = fileno(fd->fd);
    if (fstat(fd->fileno, &statinfo) < 0) {
        fclose(fd->fd);
        g_free(fd);
        return NULL;
    }
 
    dprintf("     Checking S_ISREG\n");
    if (!S_ISREG(statinfo.st_mode)) {
        fclose(fd->fd);
        g_free(fd);
        errno = EISDIR;
        return NULL;
    }
 
    dprintf("     Checking statinfo.st_size\n");
    if ((int)statinfo.st_size == 0) {
        fclose(fd->fd);
        g_free(fd);
        errno = EIO; /* More compatible with the world outside Linux */
        return NULL;
    }
 
#ifdef HAVE_SYS_MMAN_H
 
    dprintf("     Doing mmap\n");
    fd->datalen = (int)statinfo.st_size;
    fd->data    = (char*)mmap(0, statinfo.st_size, PROT_READ, MAP_PRIVATE, fd->fileno, 0);
    if (fd->data == MAP_FAILED) {
        fclose(fd->fd);
        g_free(fd);
        fd = NULL;
    }
 
#else
    /* all systems without mmap, not only MINGW32 */
 
    dprintf("     Doing calloc\n");
    fd->datalen = (int)statinfo.st_size;
    fd->data    = calloc(1, statinfo.st_size + 1);
    if (fd->data == NULL) {
        fclose(fd->fd);
        g_free(fd);
        return NULL;
    }
    if (fread((void*)fd->data, 1, statinfo.st_size, fd->fd) != statinfo.st_size) {
        fclose(fd->fd);
        g_free(fd->data);
        g_free(fd);
        return NULL;
    }
    rewind(fd->fd);
 
#endif
 
    dprintf("     Setting filename\n");
    fd->filename = g_strdup(filename);
 
    dprintf("<--- Leaving gerb_fopen\n");
    return fd;
} /* gerb_fopen */
 
int
gerb_fgetc(gerb_file_t* fd) {
 
    if (fd->ptr >= fd->datalen)
        return EOF;
 
    return (int)fd->data[fd->ptr++];
} /* gerb_fgetc */
 
int
gerb_fgetint(gerb_file_t* fd, int* len) {
    long int result;
    char*    end;
 
    errno  = 0;
    result = strtol(fd->data + fd->ptr, &end, 10);
    if (errno) {
        GERB_COMPILE_ERROR(_("Failed to read integer"));
        return 0;
    }
 
    if (len) {
        *len = end - (fd->data + fd->ptr);
    }
 
    fd->ptr = end - fd->data;
 
    if (len && (result < 0))
        *len -= 1;
 
    return (int)result;
} /* gerb_fgetint */
 
double
gerb_fgetdouble(gerb_file_t* fd) {
    double result;
    char*  end;
 
    errno  = 0;
    result = strtod(fd->data + fd->ptr, &end);
    if (errno) {
        GERB_COMPILE_ERROR(_("Failed to read double"));
        return 0.0;
    }
 
    fd->ptr = end - fd->data;
 
    return result;
} /* gerb_fgetdouble */
 
char*
gerb_fgetstring(gerb_file_t* fd, char term) {
    char* strend = NULL;
    char* newstr;
    char *i, *iend;
    int   len;
 
    iend = fd->data + fd->datalen;
    for (i = fd->data + fd->ptr; i < iend; i++) {
        if (*i == term) {
            strend = i;
            break;
        }
    }
 
    if (strend == NULL)
        return NULL;
 
    len = strend - (fd->data + fd->ptr);
 
    newstr = (char*)g_malloc(len + 1);
    if (newstr == NULL)
        return NULL;
    strncpy(newstr, fd->data + fd->ptr, len);
    newstr[len] = '\0';
    fd->ptr += len;
 
    return newstr;
} /* gerb_fgetstring */
 
void
gerb_ungetc(gerb_file_t* fd) {
    if (fd->ptr)
        fd->ptr--;
 
    return;
} /* gerb_ungetc */
 
void
gerb_fclose(gerb_file_t* fd) {
    if (fd) {
        g_free(fd->filename);
 
#ifdef HAVE_SYS_MMAN_H
        if (munmap(fd->data, fd->datalen) < 0)
            GERB_FATAL_ERROR("munmap: %s", strerror(errno));
#else
        g_free(fd->data);
#endif
        if (fclose(fd->fd) == EOF)
            GERB_FATAL_ERROR("fclose: %s", strerror(errno));
        g_free(fd);
    }
 
    return;
} /* gerb_fclose */
 
char*
gerb_find_file(const char* filename, char** paths) {
    char* curr_path     = NULL;
    char* complete_path = NULL;
    int   i;
 
#ifdef DEBUG
    if (DEBUG > 0) {
        for (i = 0; paths[i] != NULL; i++) {
            printf("%s():  paths[%d] = \"%s\"\n", __FUNCTION__, i, paths[i]);
        }
    }
#endif
 
    for (i = 0; paths[i] != NULL; i++) {
        dprintf("%s():  Try paths[%d] = \"%s\"\n", __FUNCTION__, i, paths[i]);
 
        /*
         * Environment variables start with a $ sign
         */
        if (paths[i][0] == '$') {
            char *env_name, *env_value, *tmp;
            int   len;
 
            /* Extract environment name. Remember we start with a $ */
 
            tmp = strchr(paths[i], G_DIR_SEPARATOR);
            if (tmp == NULL)
                len = strlen(paths[i]) - 1;
            else
                len = tmp - paths[i] - 1;
            env_name = (char*)g_malloc(len + 1);
            if (env_name == NULL)
                return NULL;
            strncpy(env_name, (char*)(paths[i] + 1), len);
            env_name[len] = '\0';
 
            env_value = getenv(env_name);
            dprintf(
                "%s():  Trying \"%s\" = \"%s\" from the environment\n", __FUNCTION__, env_name,
                env_value == NULL ? "(null)" : env_value
            );
 
            if (env_value == NULL) {
                curr_path = NULL;
            } else {
                curr_path = (char*)g_malloc(strlen(env_value) + strlen(&paths[i][len + 1]) + 1);
                if (curr_path == NULL)
                    return NULL;
                strcpy(curr_path, env_value);
                strcat(curr_path, &paths[i][len + 1]);
                g_free(env_name);
            }
        } else {
            curr_path = paths[i];
        }
 
        if (curr_path != NULL) {
            /*
             * Build complete path (inc. filename) and check if file exists.
             */
            complete_path = g_build_filename(curr_path, filename, NULL);
            if (complete_path == NULL)
                return NULL;
 
            if (paths[i][0] == '$') {
                g_free(curr_path);
                curr_path = NULL;
            }
 
            dprintf("%s():  Tring to access \"%s\"\n", __FUNCTION__, complete_path);
 
            if (access(complete_path, R_OK) != -1)
                break;
 
            g_free(complete_path);
            complete_path = NULL;
        }
    }
 
    if (complete_path == NULL)
        errno = ENOENT;
 
    dprintf(
        "%s():  returning complete_path = \"%s\"\n", __FUNCTION__, complete_path == NULL ? "(null)" : complete_path
    );
 
    return complete_path;
} /* gerb_find_file */