Criar aplicação com consola oculta em MinGW

Para criar uma aplicação que não tenha uma consola do Windows aberta, o que há que fazer é compila-la com a opção -mwindows, por ejemplo se tiver uma aplicação chamada code.c, então:

gcc -mwindows code.c

Instalar libcurl no entorno MinGW

1. Instalar zlib no MinGW
2. Instalar openssl no MinGW
3. Fazer o download de libcurl em http://curl.haxx.se/download.html
4. Executar os seguintes comandos:

tar xzvf curl-x.x.x.tar.gz
cd curl-x.x.x
./configure --prefix=/c/MinGW --enable-shared=no --with-ssl=/c/MinGW LIBS='-lz '
make
make install

5. Criar um ficheiro com o código:

/*****************************************************************************
 *                                  _   _ ____  _
 *  Project                     ___| | | |  _ \| |
 *                             / __| | | | |_) | |
 *                            | (__| |_| |  _ <| |___
 *                             \___|\___/|_| \_\_____|
 *
 * $Id: https.c,v 1.4 2008/05/22 21:20:09 danf Exp $
 */

#include 
#include 

int main(void)
{
  CURL *curl;
  CURLcode res;

  curl = curl_easy_init();
  if(curl) {
    curl_easy_setopt(curl, CURLOPT_URL, "https://sourceforge.net/");
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, FALSE);

#ifdef SKIP_PEER_VERIFICATION
    /*
     * If you want to connect to a site who isn't using a certificate that is
     * signed by one of the certs in the CA bundle you have, you can skip the
     * verification of the server's certificate. This makes the connection
     * A LOT LESS SECURE.
     *
     * If you have a CA cert for the server stored someplace else than in the
     * default bundle, then the CURLOPT_CAPATH option might come handy for
     * you.
     */
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
#endif

#ifdef SKIP_HOSTNAME_VERFICATION
    /*
     * If the site you're connecting to uses a different host name that what
     * they have mentioned in their server certificate's commonName (or
     * subjectAltName) fields, libcurl will refuse to connect. You can skip
     * this check, but this will make the connection less secure.
     */
    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
#endif

    res = curl_easy_perform(curl);

    /* always cleanup */
    curl_easy_cleanup(curl);
  }
  return 0;
}

6. Comprobar que o código compila correctamente com a seguinte instrução:

gcc -DCURL_STATICLIB curl_example_https.c /c/MinGW/lib/libcurl.a -lws2_32 -lwinmm -lssl -lcrypto -lgdi32 -lws2_32 -lwldap32 -lz -o curl_example_https

Instalar openssl no entorno MinGW

1. Instalar zlib em MinGW
   
2. Instalar o Strawberry em MinGW
   
3. Fazer o download do código em http://www.openssl.org/
4. Executar os seguintes comandos desde o MSYS:
   

   tar xzvf openssl-x.x.x.tar.gz
   cd openssl-x.x.x
   ./config --prefix=/c/MinGW -DMK1MF_BUILD -L/c/MinGW/lib -lz zlib no-asm
   make

5. A execução do make pode dar uns erros ao chegar rc5test.c, mdc2test.c y jpaketest.c, a solução é borra-los ;)
   
6. Agora fazer make install

Instalar Perl em Windows para ser usado com MSYS

1. Fazer o download de Strawberry em http://strawberryperl.com/
2. Fazer a instalação dele
3. Editar o arquivo /etc/fstab no MSYS (cria-lo se não existir)
4. Engadir as seguintes linhas (modifica-las para concordar com a instalação do Strawberry estar em outro lugar)
   

   C:/strawberry /opt
   C:/strawberry/perl /usr/local

5. Criar um arquivo perl_example.pl com o código seguinte
   

   print "Hello World\n";

6. Executar o MSYS e probar que o script funciona correctamente ao executar o comando:
   

   perl perl_example.pl

   
   

Instalar zlib no entorno MinGW

1. Fazer download de MinGW32 em http://www.mingw.org/wiki/MinGW
2. Fazer download MSYS em http://www.mingw.org/wiki/MSYS
3. Fazer download da última versão de zlib em http://www.zlib.net/
4. Instalar MinGW (com tudo)
5. Instalar MSYS
6. Abrir uma shell de MSYS e aceder ao diretório de zlib
7. Executar ./configure --prefix=/c/MinGW/ no shell
   
8. Executar make no shell
9. Executar make install no shell
10. Compilar o seguinte código com o comando gcc zlib_example.c -o zlib_example -lz
    

/* minigzip.c -- simulate gzip using the zlib compression library
* Copyright (C) 1995-2005 Jean-loup Gailly.
* For conditions of distribution and use, see copyright notice in zlib.h
*/

/*
* minigzip is a minimal implementation of the gzip utility. This is
* only an example of using zlib and isn't meant to replace the
* full-featured gzip. No attempt is made to deal with file systems
* limiting names to 14 or 8+3 characters, etc... Error checking is
* very limited. So use minigzip only for testing; use gzip for the
* real thing. On MSDOS, use only on file names without extension
* or in pipe mode.
*/

/* @(#) $Id$ */

#include <stdio.h>
#include "zlib.h"

#ifdef STDC
#  include <string.h>
#  include <stdlib.h>
#endif

#ifdef USE_MMAP
#  include <sys/types.h>
#  include <sys/mman.h>
#  include <sys/stat.h>
#endif

#if defined(MSDOS) || defined(OS2) || defined(WIN32) || defined(__CYGWIN__)
#  include <fcntl.h>
#  include <io.h>
#  define SET_BINARY_MODE(file) setmode(fileno(file), O_BINARY)
#else
#  define SET_BINARY_MODE(file)
#endif

#ifdef VMS
#  define unlink delete
#  define GZ_SUFFIX "-gz"
#endif
#ifdef RISCOS
#  define unlink remove
#  define GZ_SUFFIX "-gz"
#  define fileno(file) file->__file
#endif
#if defined(__MWERKS__) && __dest_os != __be_os && __dest_os != __win32_os
#  include <unix.h> /* for fileno */
#endif

#ifndef WIN32 /* unlink already in stdio.h for WIN32 */
extern int unlink OF((const char *));
#endif

#ifndef GZ_SUFFIX
#  define GZ_SUFFIX ".gz"
#endif
#define SUFFIX_LEN (sizeof(GZ_SUFFIX)-1)

#define BUFLEN      16384
#define MAX_NAME_LEN 1024

#ifdef MAXSEG_64K
#  define local static
 /* Needed for systems with limitation on stack size. */
#else
#  define local
#endif

char *prog;

void error            OF((const char *msg));
void gz_compress      OF((FILE   *in, gzFile out));
#ifdef USE_MMAP
int  gz_compress_mmap OF((FILE   *in, gzFile out));
#endif
void gz_uncompress    OF((gzFile in, FILE   *out));
void file_compress    OF((char  *file, char *mode));
void file_uncompress  OF((char  *file));
int  main             OF((int argc, char *argv[]));

/* ===========================================================================
* Display error message and exit
*/
void error(msg)
  const char *msg;
{
  fprintf(stderr, "%s: %s\n", prog, msg);
  exit(1);
}

/* ===========================================================================
* Compress input to output then close both files.
*/

void gz_compress(in, out)
  FILE   *in;
  gzFile out;
{
  local char buf[BUFLEN];
  int len;
  int err;

#ifdef USE_MMAP
  /* Try first compressing with mmap. If mmap fails (minigzip used in a
   * pipe), use the normal fread loop.
   */
  if (gz_compress_mmap(in, out) == Z_OK) return;
#endif
  for (;;) {
      len = (int)fread(buf, 1, sizeof(buf), in);
      if (ferror(in)) {
          perror("fread");
          exit(1);
      }
      if (len == 0) break;

      if (gzwrite(out, buf, (unsigned)len) != len) error(gzerror(out, &err));
  }
  fclose(in);
  if (gzclose(out) != Z_OK) error("failed gzclose");
}

#ifdef USE_MMAP /* MMAP version, Miguel Albrecht <malbrech@eso.org> */

/* Try compressing the input file at once using mmap. Return Z_OK if
* if success, Z_ERRNO otherwise.
*/
int gz_compress_mmap(in, out)
  FILE   *in;
  gzFile out;
{
  int len;
  int err;
  int ifd = fileno(in);
  caddr_t buf;    /* mmap'ed buffer for the entire input file */
  off_t buf_len;  /* length of the input file */
  struct stat sb;

  /* Determine the size of the file, needed for mmap: */
  if (fstat(ifd, &sb) < 0) return Z_ERRNO;
  buf_len = sb.st_size;
  if (buf_len <= 0) return Z_ERRNO;

  /* Now do the actual mmap: */
  buf = mmap((caddr_t) 0, buf_len, PROT_READ, MAP_SHARED, ifd, (off_t)0);
  if (buf == (caddr_t)(-1)) return Z_ERRNO;

  /* Compress the whole file at once: */
  len = gzwrite(out, (char *)buf, (unsigned)buf_len);

  if (len != (int)buf_len) error(gzerror(out, &err));

  munmap(buf, buf_len);
  fclose(in);
  if (gzclose(out) != Z_OK) error("failed gzclose");
  return Z_OK;
}
#endif /* USE_MMAP */

/* ===========================================================================
* Uncompress input to output then close both files.
*/
void gz_uncompress(in, out)
  gzFile in;
  FILE   *out;
{
  local char buf[BUFLEN];
  int len;
  int err;

  for (;;) {
      len = gzread(in, buf, sizeof(buf));
      if (len < 0) error (gzerror(in, &err));
      if (len == 0) break;

      if ((int)fwrite(buf, 1, (unsigned)len, out) != len) {
          error("failed fwrite");
      }
  }
  if (fclose(out)) error("failed fclose");

  if (gzclose(in) != Z_OK) error("failed gzclose");
}


/* ===========================================================================
* Compress the given file: create a corresponding .gz file and remove the
* original.
*/
void file_compress(file, mode)
  char  *file;
  char  *mode;
{
  local char outfile[MAX_NAME_LEN];
  FILE  *in;
  gzFile out;

  strcpy(outfile, file);
  strcat(outfile, GZ_SUFFIX);

  in = fopen(file, "rb");
  if (in == NULL) {
      perror(file);
      exit(1);
  }
  out = gzopen(outfile, mode);
  if (out == NULL) {
      fprintf(stderr, "%s: can't gzopen %s\n", prog, outfile);
      exit(1);
  }
  gz_compress(in, out);

  unlink(file);
}


/* ===========================================================================
* Uncompress the given file and remove the original.
*/
void file_uncompress(file)
  char  *file;
{
  local char buf[MAX_NAME_LEN];
  char *infile, *outfile;
  FILE  *out;
  gzFile in;
  uInt len = (uInt)strlen(file);

  strcpy(buf, file);

  if (len > SUFFIX_LEN && strcmp(file+len-SUFFIX_LEN, GZ_SUFFIX) == 0) {
      infile = file;
      outfile = buf;
      outfile[len-3] = '\0';
  } else {
      outfile = file;
      infile = buf;
      strcat(infile, GZ_SUFFIX);
  }
  in = gzopen(infile, "rb");
  if (in == NULL) {
      fprintf(stderr, "%s: can't gzopen %s\n", prog, infile);
      exit(1);
  }
  out = fopen(outfile, "wb");
  if (out == NULL) {
      perror(file);
      exit(1);
  }

  gz_uncompress(in, out);

  unlink(infile);
}


/* ===========================================================================
* Usage:  minigzip [-d] [-f] [-h] [-r] [-1 to -9] [files...]
*   -d : decompress
*   -f : compress with Z_FILTERED
*   -h : compress with Z_HUFFMAN_ONLY
*   -r : compress with Z_RLE
*   -1 to -9 : compression level
*/

int main(argc, argv)
  int argc;
  char *argv[];
{
  int uncompr = 0;
  gzFile file;
  char outmode[20];

  strcpy(outmode, "wb6 ");

  prog = argv[0];
  argc--, argv++;

  while (argc > 0) {
    if (strcmp(*argv, "-d") == 0)
      uncompr = 1;
    else if (strcmp(*argv, "-f") == 0)
      outmode[3] = 'f';
    else if (strcmp(*argv, "-h") == 0)
      outmode[3] = 'h';
    else if (strcmp(*argv, "-r") == 0)
      outmode[3] = 'R';
    else if ((*argv)[0] == '-' && (*argv)[1] >= '1' && (*argv)[1] <= '9' &&
             (*argv)[2] == 0)
      outmode[2] = (*argv)[1];
    else
      break;
    argc--, argv++;
  }
  if (outmode[3] == ' ')
      outmode[3] = 0;
  if (argc == 0) {
      SET_BINARY_MODE(stdin);
      SET_BINARY_MODE(stdout);
      if (uncompr) {
          file = gzdopen(fileno(stdin), "rb");
          if (file == NULL) error("can't gzdopen stdin");
          gz_uncompress(file, stdout);
      } else {
          file = gzdopen(fileno(stdout), outmode);
          if (file == NULL) error("can't gzdopen stdout");
          gz_compress(stdin, file);
      }
  } else {
      do {
          if (uncompr) {
              file_uncompress(*argv);
          } else {
              file_compress(*argv, outmode);
          }
      } while (argv++, --argc);
  }
  return 0;
}

1. E agora comprobar que ao executar zlib_example.exe file.ext se gera file.ext.gz que é o arquivo original comprimido. E que ao fazer zlib_example.exe -d file.ext.gz voltamos ter o arquivo original file.ext