need to fix argument in the main function, but how ?

[netlink1987]

Hi all,
I need to fix some arguments or defualt arguments in the main function below, but i don't know how, all what i've test does not work, thanks for your help. It's ffmpeg.c source and i need to fix input stream and output stream as follow:
ffmpeg -i rtsp://host/live -f flv rtmp://remotehost/live

int main(int argc, char **argv)
{
int i, ret;
BenchmarkTimeStamps ti;

init_dynload();

register_exit(ffmpeg_cleanup);

setvbuf(stderr,NULL,_IONBF,0);


av_log_set_flags(AV_LOG_SKIP_REPEATED);
parse_loglevel(argc, argv, options);


if(argc>1 && !strcmp(argv[1], "-d")){
run_as_daemon=1;
av_log_set_callback(log_callback_null);
argc--;
argv++;
}



#if CONFIG_AVDEVICE
avdevice_register_all();
#endif
avformat_network_init();

show_banner(argc, argv, options);

/* parse options and open all input/output files */
ret = ffmpeg_parse_options(argc, argv);
if (ret < 0)
exit_program(1);

if (nb_output_files <= 0 && nb_input_files == 0) {
show_usage();
av_log(NULL, AV_LOG_WARNING, "Use -h to get full help or, even better, run 'man %s'\n", program_name);
exit_program(1);
}

/* file converter / grab */
if (nb_output_files <= 0) {
av_log(NULL, AV_LOG_FATAL, "At least one output file must be specified\n");
exit_program(1);
}

for (i = 0; i < nb_output_files; i++) {
if (strcmp(output_files[i]->ctx->oformat->name, "rtp"))
want_sdp = 0;
}

/* current_time = ti = get_benchmark_time_stamps();*/
if (transcode() < 0)
exit_program(1);
if (do_benchmark) {
int64_t utime, stime, rtime;
current_time = get_benchmark_time_stamps();
utime = current_time.user_usec - ti.user_usec;
stime = current_time.sys_usec - ti.sys_usec;
rtime = current_time.real_usec - ti.real_usec;
av_log(NULL, AV_LOG_INFO,
"bench: utime=%0.3fs stime=%0.3fs rtime=%0.3fs\n",
utime / 1000000.0, stime / 1000000.0, rtime / 1000000.0);
}

av_log(NULL, AV_LOG_DEBUG, "%"PRIu64" frames successfully decoded, %"PRIu64" decoding errors\n",
decode_error_stat[0], decode_error_stat[1]);
if ((decode_error_stat[0] + decode_error_stat[1]) * max_error_rate < decode_error_stat[1])
exit_program(69);

exit_program(received_nb_signals ? 255 : main_return_code);
return main_return_code;
}

[Salem]

TBH, I'd do this using a 1-line bash script.

#!/bin/bash
ffmpeg -i rtsp://host/live -f flv rtmp://remotehost/live $*

But if you really want to maul the code about, then you could do

char **newargv = malloc(argc+5,sizeof(*newargv));
newargv[0] = argv[0];
newargv[1] = "-i";
newargv[2] = "rtsp://host/live";
//
for ( int i = 1, j = 6 ; i < argc ; i++, j++ ) newargc[j] = argv[i];

[netlink1987]

Thank you salemn for your help.

Yes i don't want a shell script for security reason. I really need to hardcode this in the ffmpeg source.

When i try the code you gave me i cannot compile:

int main(int argc, char **argv){
    int i, ret;
    BenchmarkTimeStamps ti;


    char **newargv = malloc(argc+5,sizeof(*newargv));
    newargv[0] = argv[0];
    newargv[1] = "-i";
    newargv[2] = "rtsp://host/live";


    for ( int i = 1, j = 6 ; i < argc ; i++, j++ ) newargc[j] = argv[i]


    init_dynload();


    register_exit(ffmpeg_cleanup);


    setvbuf(stderr,NULL,_IONBF,0);




    av_log_set_flags(AV_LOG_SKIP_REPEATED);
    parse_loglevel(argc, argv, options);

fftools/ffmpeg.c: In function âdo_streamcopyâ:
fftools/ffmpeg.c:2074:5: warning: âav_copy_packet_side_dataâ is deprecated [-Wdeprecated-declarations]
av_copy_packet_side_data(&opkt, pkt);
^~~~~~~~~~~~~~~~~~~~~~~~
In file included from ./libavformat/avformat.h:317:0,
from fftools/ffmpeg.c:43:
./libavcodec/avcodec.h:4463:5: note: declared here
int av_copy_packet_side_data(AVPacket *dst, const AVPacket *src);
^~~~~~~~~~~~~~~~~~~~~~~~
fftools/ffmpeg.c: In function âinit_output_streamâ:
fftools/ffmpeg.c:3545:9: warning: âavcodec_copy_contextâ is deprecated [-Wdeprecated-declarations]
ret = avcodec_copy_context(ost->st->codec, ost->enc_ctx);
^~~
In file included from ./libavformat/avformat.h:317:0,
from fftools/ffmpeg.c:43:
./libavcodec/avcodec.h:4235:5: note: declared here
int avcodec_copy_context(AVCodecContext *dest, const AVCodecContext *src);
^~~~~~~~~~~~~~~~~~~~
fftools/ffmpeg.c:3545:9: warning: âcodecâ is deprecated [-Wdeprecated-declarations]
ret = avcodec_copy_context(ost->st->codec, ost->enc_ctx);
^~~
In file included from fftools/ffmpeg.c:43:0:
./libavformat/avformat.h:885:21: note: declared here
AVCodecContext *codec;
^~~~~
fftools/ffmpeg.c:3591:9: warning: âcodecâ is deprecated [-Wdeprecated-declarations]
ost->st->codec->codec= ost->enc_ctx->codec;
^~~
In file included from fftools/ffmpeg.c:43:0:
./libavformat/avformat.h:885:21: note: declared here
AVCodecContext *codec;
^~~~~
fftools/ffmpeg.c: In function âcheck_keyboard_interactionâ:
fftools/ffmpeg.c:3974:13: warning: âcodecâ is deprecated [-Wdeprecated-declarations]
debug = input_streams[0]->st->codec->debug<<1;
^~~~~
In file included from fftools/ffmpeg.c:43:0:
./libavformat/avformat.h:885:21: note: declared here
AVCodecContext *codec;
^~~~~
fftools/ffmpeg.c:3997:13: warning: âcodecâ is deprecated [-Wdeprecated-declarations]
input_streams[i]->st->codec->debug = debug;
^~~~~~~~~~~~~
In file included from fftools/ffmpeg.c:43:0:
./libavformat/avformat.h:885:21: note: declared here
AVCodecContext *codec;
^~~~~
fftools/ffmpeg.c: In function âmainâ:
fftools/ffmpeg.c:4848:22: error: too many arguments to function âmallocâ

TBH, I'd do this using a 1-line bash script.

#!/bin/bash
ffmpeg -i rtsp://host/live -f flv rtmp://remotehost/live $*

But if you really want to maul the code about, then you could do

char **newargv = malloc(argc+5,sizeof(*newargv));
newargv[0] = argv[0];
newargv[1] = "-i";
newargv[2] = "rtsp://host/live";
//
for ( int i = 1, j = 6 ; i < argc ; i++, j++ ) newargc[j] = argv[i];

[Salem]

Yeah, should be
malloc((argc+5)*sizeof(*newargv));

[netlink1987]

got sorry ..... still errors on compile:

fftools/ffmpeg.c:4850:52: error: ânewargcâ undeclared (first use in this function); did you mean ânewargvâ?
for ( int i = 1, j = 3 ; i < argc ; i++, j++ ) newargc[j] = argv[i]
^~~~~~~
newargv
fftools/ffmpeg.c:4850:52: note: each undeclared identifier is reported only once for each function it appears in
fftools/ffmpeg.c:4851:5: error: expected â;â before âintâ
int i, ret;
^~~
fftools/ffmpeg.c:4852:5: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
BenchmarkTimeStamps ti;
^~~~~~~~~~~~~~~~~~~
fftools/ffmpeg.c:4882:5: error: âretâ undeclared (first use in this function); did you mean âcreatâ?
ret = ffmpeg_parse_options(argc, argv);
^~~
creat
fftools/ffmpeg.c:4898:10: error: âiâ undeclared (first use in this function); did you mean âtiâ?
for (i = 0; i < nb_output_files; i++) {
^
ti

[cronus]

The error about newargc is very clear, I think you can fix the typo yourself. And for the other errors, I believe those can be fixed by moving the declarations to the beginning of function.

[Salem]

Converting C99 code to C90 is left as an exercise for the reader.

Since you didn't say "I'm a completely clueless noob", I assumed a basic modicum of skill.