SSH ChannelReceiveUntilMatchN (Match Any of Several Prompts)

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Demonstrates ChannelReceiveUntilMatchN, which receives until any one of several patterns is matched. This is useful when driving an interactive session where the shell prompt differs from device to device.

Note: This example deliberately requests a PTY. Matching a shell prompt only works in an interactive session — without a PTY the shell runs non-interactively and never prints a prompt at all. For scripted use, omit the PTY and match on a marker your own command echoes.

#import <CkoSsh.h>
#import <CkoStringArray.h>
#import <NSString.h>

BOOL success = NO;

//  This example requires the Chilkat API to have been previously unlocked.
//  See Global Unlock Sample for sample code.

//  Demonstrates ChannelReceiveUntilMatchN, which receives until ANY one of several patterns is
//  matched.  This is useful when driving an interactive session where the shell prompt varies
//  from device to device.
//  
//  Note: This example deliberately DOES request a PTY.  Matching a shell prompt only works in an
//  interactive session -- without a PTY the shell runs non-interactively and never prints a
//  prompt at all.  For scripted use where no prompt is needed, omit the PTY and match on a
//  marker your own command echoes instead.

CkoSsh *ssh = [[CkoSsh alloc] init];

//  The remote shell prompt may be any of these, depending on the device.
CkoStringArray *saPrompts = [[CkoStringArray alloc] init];
[saPrompts Append: @"~$"];
[saPrompts Append: @"mars#"];
[saPrompts Append: @"jupiter%"];
[saPrompts Append: @"chilkat$"];
[saPrompts Append: @"admin>"];

NSString *hostname = @"ssh.example.com";
int port = 22;
success = [ssh Connect: hostname port: [NSNumber numberWithInt: port]];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  Normally you would not hard-code the password in source.  You should instead obtain it
//  from an interactive prompt, environment variable, or a secrets vault.
NSString *password = @"mySshPassword";

success = [ssh AuthenticatePw: @"mySshLogin" password: password];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

int channelNum = [[ssh OpenSessionChannel] intValue];
if (channelNum < 0) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  Request a pseudo-terminal so the shell runs interactively and prints prompts.  A "dumb"
//  terminal is used so that ANSI escape sequences are not mixed into the output.
NSString *termType = @"dumb";
int widthInChars = 120;
int heightInChars = 40;
int pixWidth = 0;
int pixHeight = 0;
success = [ssh SendReqPty: [NSNumber numberWithInt: channelNum] xTermEnvVar: termType widthInChars: [NSNumber numberWithInt: widthInChars] heightInRows: [NSNumber numberWithInt: heightInChars] pixWidth: [NSNumber numberWithInt: pixWidth] pixHeight: [NSNumber numberWithInt: pixHeight]];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

success = [ssh SendReqShell: [NSNumber numberWithInt: channelNum]];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  IMPORTANT: Set a read timeout before receiving until a match.  ReadTimeoutMs defaults to 0,
//  which means no limit -- without it, this call waits forever if the received data never
//  contains a match.
ssh.ReadTimeoutMs = [NSNumber numberWithInt:15000];

BOOL caseSensitive = YES;

//  Read the initial login text up to the first prompt.
success = [ssh ChannelReceiveUntilMatchN: [NSNumber numberWithInt: channelNum] matchPatterns: saPrompts charset: @"utf-8" caseSensitive: caseSensitive];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSString *cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"utf-8"];
if (ssh.LastMethodSuccess == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

//  ---- 1st command ----
success = [ssh ChannelSendString: [NSNumber numberWithInt: channelNum] strData: @"cd /tmp\n" charset: @"utf-8"];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

success = [ssh ChannelReceiveUntilMatchN: [NSNumber numberWithInt: channelNum] matchPatterns: saPrompts charset: @"utf-8" caseSensitive: caseSensitive];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

//  Retrieving the text also clears the receive buffer, which matters: if a prompt were left
//  buffered, the next receive would match it immediately and return the wrong output.
cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"utf-8"];
if (ssh.LastMethodSuccess == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

//  ---- 2nd command ----
success = [ssh ChannelSendString: [NSNumber numberWithInt: channelNum] strData: @"ls\n" charset: @"utf-8"];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

success = [ssh ChannelReceiveUntilMatchN: [NSNumber numberWithInt: channelNum] matchPatterns: saPrompts charset: @"utf-8" caseSensitive: caseSensitive];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"utf-8"];
if (ssh.LastMethodSuccess == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

//  Finish the session.
success = [ssh ChannelSendEof: [NSNumber numberWithInt: channelNum]];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

success = [ssh ChannelReceiveToClose: [NSNumber numberWithInt: channelNum]];
if (success == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

cmdOutput = [ssh GetReceivedText: [NSNumber numberWithInt: channelNum] charset: @"utf-8"];
if (ssh.LastMethodSuccess == NO) {
    NSLog(@"%@",ssh.LastErrorText);
    return;
}

NSLog(@"%@",cmdOutput);

[ssh Disconnect];