/*
 * Useful functions for winegcc
 *
 * Copyright 2000 Francois Gouget
 * Copyright 2002 Dimitrie O. Paun
 * Copyright 2003 Richard Cohen
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */
#include "config.h"
#include "wine/port.h"

#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <errno.h>

#include "utils.h"

#if !defined(min)
# define min(x,y) (((x) < (y)) ? (x) : (y))
#endif

#if defined(_WIN32) && !defined(__CYGWIN__)
# define PATH_SEPARATOR ';'
#else
# define PATH_SEPARATOR ':'
#endif

int verbose = 0;

void error(const char* s, ...)
{
    va_list ap;
    
    va_start(ap, s);
    fprintf(stderr, "winegcc: ");
    vfprintf(stderr, s, ap);
    va_end(ap);
    exit(2);
}

void* xmalloc(size_t size)
{
    void* p;

    if ((p = malloc (size)) == NULL)
	error("Could not malloc %d bytes\n", size);

    return p;
}

void *xrealloc(void* p, size_t size)
{
    void* p2 = realloc (p, size);
    if (size && !p2)
	error("Could not realloc %d bytes\n", size);

    return p2;
}

char *xstrdup( const char *str )
{
    char *res = strdup( str );
    if (!res) error("Virtual memory exhausted.\n");
    return res;
}

int strendswith(const char* str, const char* end)
{
    int l = strlen(str);
    int m = strlen(end);
   
    return l >= m && strcmp(str + l - m, end) == 0; 
}

char* strmake(const char* fmt, ...)
{
    int n;
    size_t size = 100;
    va_list ap;

    while (1)
    {
        char *p = xmalloc (size);
        va_start(ap, fmt);
	n = vsnprintf (p, size, fmt, ap);
	va_end(ap);
        if (n == -1) size *= 2;
        else if ((size_t)n >= size) size = n + 1;
        else return p;
        free(p);
    }
}

strarray* strarray_alloc(void)
{
    strarray* arr = xmalloc(sizeof(*arr));
    arr->maximum = arr->size = 0;
    arr->base = NULL;
    return arr;
}

void strarray_free(strarray* arr)
{
    free(arr->base);
    free(arr);
}

void strarray_add(strarray* arr, const char* str)
{
    if (arr->size == arr->maximum)
    {
	arr->maximum += 10;
	arr->base = xrealloc(arr->base, sizeof(*(arr->base)) * arr->maximum);
    }
    arr->base[arr->size++] = str;
}

void strarray_del(strarray* arr, unsigned int i)
{
    if (i >= arr->size) error("Invalid index i=%d\n", i);
    memmove(&arr->base[i], &arr->base[i + 1], (arr->size - i - 1) * sizeof(arr->base[0]));
    arr->size--;
}

void strarray_addall(strarray* arr, const strarray* from)
{
    unsigned int i;

    for (i = 0; i < from->size; i++)
	strarray_add(arr, from->base[i]);
}

strarray* strarray_dup(const strarray* arr)
{
    strarray* dup = strarray_alloc();
    unsigned int i;

    for (i = 0; i < arr->size; i++)
	strarray_add(dup, arr->base[i]);

    return dup;
}

strarray* strarray_fromstring(const char* str, const char* delim)
{
    strarray* arr = strarray_alloc();
    char* buf = strdup(str);
    const char* tok;

    for(tok = strtok(buf, delim); tok; tok = strtok(0, delim))
	strarray_add(arr, strdup(tok));

    free(buf);
    return arr;
}

char* strarray_tostring(const strarray* arr, const char* sep)
{
    char *str, *newstr;
    unsigned int i;

    str = strmake("%s", arr->base[0]);
    for (i = 1; i < arr->size; i++)
    {
	newstr = strmake("%s%s%s", str, sep, arr->base[i]);
	free(str);
	str = newstr;
    }

    return str;
}

char* get_basename(const char* file)
{
    const char* name;
    char *base_name, *p;

    if ((name = strrchr(file, '/'))) name++;
    else name = file;

    base_name = strdup(name);
    if ((p = strrchr(base_name, '.'))) *p = 0;

    return base_name;
}

void create_file(const char* name, int mode, const char* fmt, ...)
{
    va_list ap;
    FILE *file;

    if (verbose) printf("Creating file %s\n", name);
    va_start(ap, fmt);
    if ( !(file = fopen(name, "w")) )
	error("Unable to open %s for writing\n", name);
    vfprintf(file, fmt, ap);
    va_end(ap);
    fclose(file);
    chmod(name, mode);
}

file_type get_file_type(const char* filename)
{
    /* see tools/winebuild/res32.c: check_header for details */
    static const char res_sig[] = { 0,0,0,0, 32,0,0,0, 0xff,0xff, 0,0, 0xff,0xff, 0,0, 0,0,0,0, 0,0, 0,0, 0,0,0,0, 0,0,0,0 };
    static const char elf_sig[4] = "\177ELF";
    char buf[sizeof(res_sig)];
    int fd, cnt;

    fd = open( filename, O_RDONLY );
    if (fd == -1) return file_na;
    cnt = read(fd, buf, sizeof(buf));
    close( fd );
    if (cnt == -1) return file_na;

    if (cnt == sizeof(res_sig) && !memcmp(buf, res_sig, sizeof(res_sig))) return file_res;
    if (strendswith(filename, ".o")) return file_obj;
    if (strendswith(filename, ".a")) return file_arh;
    if (strendswith(filename, ".res")) return file_res;
    if (strendswith(filename, ".so")) return file_so;
    if (strendswith(filename, ".dylib")) return file_so;
    if (strendswith(filename, ".def")) return file_def;
    if (strendswith(filename, ".spec")) return file_spec;
    if (strendswith(filename, ".rc")) return file_rc;
    if (cnt >= sizeof(elf_sig) && !memcmp(buf, elf_sig, sizeof(elf_sig))) return file_so;  /* ELF lib */
    if (cnt >= sizeof(unsigned int) &&
        (*(unsigned int *)buf == 0xfeedface || *(unsigned int *)buf == 0xcefaedfe ||
         *(unsigned int *)buf == 0xfeedfacf || *(unsigned int *)buf == 0xcffaedfe))
        return file_so; /* Mach-O lib */

    return file_other;
}

static char* try_lib_path(const char* dir, const char* pre, 
			  const char* library, const char* ext,
			  file_type expected_type)
{
    char *fullname;
    file_type type;

    /* first try a subdir named from the library we are looking for */
    fullname = strmake("%s/%s/%s%s%s", dir, library, pre, library, ext);
    if (verbose > 1) fprintf(stderr, "Try %s...", fullname);
    type = get_file_type(fullname);
    if (verbose > 1) fprintf(stderr, type == expected_type ? "FOUND!\n" : "no\n");
    if (type == expected_type) return fullname;
    free( fullname );

    fullname = strmake("%s/%s%s%s", dir, pre, library, ext);
    if (verbose > 1) fprintf(stderr, "Try %s...", fullname);
    type = get_file_type(fullname);
    if (verbose > 1) fprintf(stderr, type == expected_type ? "FOUND!\n" : "no\n");
    if (type == expected_type) return fullname;
    free( fullname );
    return 0; 
}

static file_type guess_lib_type(enum target_platform platform, const char* dir,
                                const char* library, const char *suffix, char** file)
{
    if (platform != PLATFORM_WINDOWS && platform != PLATFORM_MINGW && platform != PLATFORM_CYGWIN)
    {
        /* Unix shared object */
        if ((*file = try_lib_path(dir, "lib", library, ".so", file_so)))
            return file_so;

        /* Mach-O (Darwin/Mac OS X) Dynamic Library behaves mostly like .so */
        if ((*file = try_lib_path(dir, "lib", library, ".dylib", file_so)))
            return file_so;

        /* Windows DLL */
        if ((*file = try_lib_path(dir, "lib", library, ".def", file_def)))
            return file_dll;
    }

    /* static archives */
    if ((*file = try_lib_path(dir, "lib", library, suffix, file_arh)))
	return file_arh;

    return file_na;
}

file_type get_lib_type(enum target_platform platform, strarray* path, const char *library,
                       const char *suffix, char** file)
{
    unsigned int i;

    if (!suffix) suffix = ".a";
    for (i = 0; i < path->size; i++)
    {
        file_type type = guess_lib_type(platform, path->base[i], library, suffix, file);
	if (type != file_na) return type;
    }
    return file_na;
}

const char *find_binary( const strarray* prefix, const char *name )
{
    char *file_name, *args;
    static strarray *path;
    unsigned int i;

    if (strchr( name, '/' )) return name;

    file_name = xstrdup( name );
    if ((args = strchr( file_name, ' ' ))) *args++ = 0;

    if (prefix)
    {
        for (i = 0; i < prefix->size; i++)
        {
            struct stat st;
            char *prog = strmake( "%s/%s%s", prefix->base[i], file_name, EXEEXT );
            if (stat( prog, &st ) == 0 && S_ISREG( st.st_mode ) && (st.st_mode & 0111))
                return args ? strmake( "%s %s", prog, args ) : prog;
            free( prog );
        }
    }
    if (!path)
    {
        path = strarray_alloc();

        /* then append the PATH directories */
        if (getenv( "PATH" ))
        {
            char *p = xstrdup( getenv( "PATH" ));
            while (*p)
            {
                strarray_add( path, p );
                while (*p && *p != PATH_SEPARATOR) p++;
                if (!*p) break;
                *p++ = 0;
            }
        }
    }
    return prefix == path ? NULL : find_binary( path, name );
}

int spawn(const strarray* prefix, const strarray* args, int ignore_errors)
{
    unsigned int i;
    int status;
    strarray* arr = strarray_dup(args);
    const char** argv;
    char* prog = 0;

    strarray_add(arr, NULL);
    argv = arr->base;
    argv[0] = find_binary( prefix, argv[0] );

    if (verbose)
    {
	for(i = 0; argv[i]; i++)
	{
	    if (strpbrk(argv[i], " \t\n\r")) printf("\"%s\" ", argv[i]);
	    else printf("%s ", argv[i]);
	}
	printf("\n");
    }

    if ((status = _spawnvp( _P_WAIT, argv[0], argv)) && !ignore_errors)
    {
	if (status > 0) error("%s failed\n", argv[0]);
	else perror("winegcc");
	exit(3);
    }

    free(prog);
    strarray_free(arr);
    return status;
}

/* xorshift* random generator. Source: https://en.wikipedia.org/wiki/Xorshift#xorshift* */
static uint64_t pseudorandom_state = 1;
static const char* pseudorandom_source = NULL;
static size_t pseudorandom_source_size = 0;

static uint64_t pseudorandom_algo(uint64_t* generator_state, uint64_t add_to_state)
{
    uint64_t tmp = (*generator_state) + add_to_state;
    tmp ^= tmp >> 12;
    tmp ^= tmp << 25;
    tmp ^= tmp >> 27;
    (*generator_state) = tmp;
    return tmp * UINT64_C(0x2545F4914F6CDD1D);
}

uint64_t pseudorandom(uint64_t add_to_state)
{
    return pseudorandom_algo(&pseudorandom_state, add_to_state);
}

char pseudorandom_char(void)
{
    char tmp;
    tmp = (char) (pseudorandom(0) % 62);
    if (tmp < 10)
    {
        return '0' + tmp;
    }
    else if (tmp < 36)
    {
        return 'A' + (tmp - 10);
    }
    else
    {
        return 'a' + (tmp - 36);
    }
}

int pseudorandom_tempfile(char* file)
{
    /* variables */
    int result;

    int counter;
    char *filename_pos;

    char *debug_filename;
    FILE *debug_file;

    /* replaces Xs */
    for (filename_pos = file; (*filename_pos) != 0; filename_pos++)
    {
        if ((*filename_pos) == 'X')
        {
            (*filename_pos) = pseudorandom_char();
        }
    }

    /* try to open file */
    counter = 0;
    do
    {
        result = open(file, O_CREAT | O_EXCL | O_RDWR, 0600);
        if (result != -1)
        {
            break;
        }
        sleep(5);
        counter++;
    } while (counter <= 12);

    /* add deebug info */
    if ((result != -1) && (getenv("SOURCE_RANDOM_DEBUG") != NULL))
    {
        debug_filename = strmake("%s.random_debug", file);
        debug_file = fopen(debug_filename, "wb");
        fwrite(pseudorandom_source, 1, pseudorandom_source_size, debug_file);
        fclose(debug_file);
        free(debug_filename);
    }
    return result;
}

void init_random_generator(int argc, char **argv)
{
    /* variables */
    uint64_t generator_state;

    void *argv_data;
    size_t argv_size;

    unsigned int counter;
    void *env_data;
    size_t env_size;
    char **tmp_envs;

    char *buffer_pos;
    char **env;
    size_t length;

    unsigned int i;
    size_t j;

    /* process environment */
    generator_state = 1;
    env_size = 0;
    {
        /* sort environment variables */
        counter = 0;
        for (env = environ; (*env) != NULL; env++)
        {
            counter++;
            env_size += strlen(*env) + 1;
        }
        tmp_envs = (char**) malloc(sizeof(char*) * counter);
        for (i = 0; i < counter; i++)
        {
            tmp_envs[i] = (char*) (environ[i]);
        }
        qsort(tmp_envs, counter, sizeof(char*), (int(*)(const void*, const void*)) &strcmp);

        /* and copy them */
        env_data = malloc(env_size * sizeof(char));
        buffer_pos = env_data;
        for (i = 0; i < counter; i++)
        {
            length = strlen(tmp_envs[i]) + 1;
            memcpy(buffer_pos, tmp_envs[i], length);
            buffer_pos += length;
        }

        /* add sorted environment to random generator */
        for (j = 0; j < env_size; j++)
        {
            pseudorandom_algo(&generator_state, ((unsigned char*) env_data)[j]);
        }

        /* free temp environment */
        free(tmp_envs);
    }

    /* copy argv */
    argv_size = 0;
    for (i = 0; i < argc; i++)
    {
        argv_size += strlen(argv[i]) + 1;
    }
    argv_data = malloc(sizeof(char) * argv_size);
    buffer_pos = argv_data;
    for (i = 0; i < argc; i++)
    {
        length = strlen(argv[i]) + 1;
        memcpy(buffer_pos, argv[i], length);
        buffer_pos += length;
    }

    /* add arguments to gnerator */
    for (j = 0; j < argv_size; j++)
    {
        pseudorandom_algo(&generator_state, ((unsigned char*) argv_data)[j]);
    }

    /* add debug if required */
    if (getenv("SOURCE_RANDOM_DEBUG") != NULL)
    {
        /* gen field */
        pseudorandom_source_size = env_size + argv_size + sizeof(generator_state);
        buffer_pos = malloc(sizeof(char) * pseudorandom_source_size);
        pseudorandom_source = buffer_pos;

        /* copy data into it */
        memcpy(buffer_pos, env_data, env_size);
        buffer_pos += env_size;
        memcpy(buffer_pos, argv_data, argv_size);
        buffer_pos += argv_size;
        memcpy(buffer_pos, &generator_state, sizeof(generator_state));
    }

    /* set state and free rest */
    free(env_data);
    free(argv_data);
    pseudorandom_state = generator_state;
}