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Signed-off-by: Nico Schottelius <nico@ikn.schottelius.org>
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Nico Schottelius 2009-10-21 23:25:04 +02:00
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docs/a-small-introduction-for-using-gpgme/gpgme-export-all.c Normal file
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/* gpgme-example1:
*
* Nico Schottelius, 2007-08-05, GPLv3
*
* export all public keys
*/
#include <gpgme.h> /* gpgme */
#include <stdio.h> /* printf */
#include <unistd.h> /* write */
#include <errno.h> /* errno */
#include <locale.h> /* locale support */
#define SIZE 1024
/* USE -D_FILE_OFFSET_BITS=64 (at least) on Debian! */
int main()
{
char *p;
char buf[SIZE];
size_t read_bytes;
int tmp;
gpgme_ctx_t ceofcontext;
gpgme_error_t err;
gpgme_data_t data;
gpgme_engine_info_t enginfo;
/* The function `gpgme_check_version' must be called before any other
* function in the library, because it initializes the thread support
* subsystem in GPGME. (from the info page) */
setlocale (LC_ALL, "");
p = (char *) gpgme_check_version(NULL);
printf("version=%s\n",p);
/* set locale, because tests do also */
gpgme_set_locale(NULL, LC_CTYPE, setlocale (LC_CTYPE, NULL));
/* check for OpenPGP support */
err = gpgme_engine_check_version(GPGME_PROTOCOL_OpenPGP);
if(err != GPG_ERR_NO_ERROR) return 1;
p = (char *) gpgme_get_protocol_name(GPGME_PROTOCOL_OpenPGP);
printf("Protocol name: %s\n",p);
/* get engine information */
err = gpgme_get_engine_info(&enginfo);
if(err != GPG_ERR_NO_ERROR) return 2;
printf("file=%s, home=%s\n",enginfo->file_name,enginfo->home_dir);
/* create our own context */
err = gpgme_new(&ceofcontext);
if(err != GPG_ERR_NO_ERROR) return 3;
/* set protocol to use in our context */
err = gpgme_set_protocol(ceofcontext,GPGME_PROTOCOL_OpenPGP);
if(err != GPG_ERR_NO_ERROR) return 4;
/* set engine info in our context; I changed it for ceof like this:
err = gpgme_ctx_set_engine_info (ceofcontext, GPGME_PROTOCOL_OpenPGP,
"/usr/bin/gpg","/home/user/nico/.ceof/gpg/");
but I'll use standard values for this example: */
err = gpgme_ctx_set_engine_info (ceofcontext, GPGME_PROTOCOL_OpenPGP,
enginfo->file_name,enginfo->home_dir);
if(err != GPG_ERR_NO_ERROR) return 5;
/* do ascii armor data, so output is readable in console */
gpgme_set_armor(ceofcontext, 1);
/* create buffer for data exchange with gpgme*/
err = gpgme_data_new(&data);
if(err != GPG_ERR_NO_ERROR) return 6;
/* set encoding for the buffer... */
err = gpgme_data_set_encoding(data,GPGME_DATA_ENCODING_ARMOR);
if(err != GPG_ERR_NO_ERROR) return 7;
/* verify encoding: not really needed */
tmp = gpgme_data_get_encoding(data);
if(tmp == GPGME_DATA_ENCODING_ARMOR) {
printf("encode ok\n");
} else {
printf("encode broken\n");
}
/* with NULL it exports all public keys */
err = gpgme_op_export(ceofcontext,NULL,0,data);
if(err != GPG_ERR_NO_ERROR) return 8;
read_bytes = gpgme_data_seek (data, 0, SEEK_END);
printf("end is=%d\n",read_bytes);
if(read_bytes == -1) {
p = (char *) gpgme_strerror(errno);
printf("data-seek-err: %s\n",p);
return 9;
}
read_bytes = gpgme_data_seek (data, 0, SEEK_SET);
printf("start is=%d (should be 0)\n",read_bytes);
/* write keys to stderr */
while ((read_bytes = gpgme_data_read (data, buf, SIZE)) > 0) {
write(2,buf,read_bytes);
}
/* append \n, so that there is really a line feed */
write(2,"\n",1);
/* free data */
gpgme_data_release(data);
/* free context */
gpgme_release(ceofcontext);
return 0;
}