CLI : monitor command

src/cli.c

@@ -1,5 +1,5 @@
 //=-------------------------------------------------------------------------=//
-//  Command line interface management module                                 //
+//  Command line interface main file                                         //
 //                                                                           //
 //  Copyright © 2021 The Gem-graph Project                                   //
 //                                                                           //
@@ -22,11 +22,13 @@
 #include "../include/base.h"
 
 #include <sys/socket.h>
+#include <sys/ioctl.h>
 #include <arpa/inet.h>
 #include <netdb.h>
 #include <sys/socket.h>
 #include <unistd.h>
 #include <termios.h>
+#include <fcntl.h>
 
 #define SEND_BUFFER_SIZE 80
 #define RECEIVE_BUFFER_SIZE 80 * 24
@@ -43,6 +45,7 @@
 #define KEY_ARROW_LEFT 68
 #define KEY_DELETE 127
 
+#define C_CLEARSCREEN "\e[2J"
 #define C_CLEARLINE "\e[2K"
 #define C_CURSORLEFT "\e[1D"
 #define C_CURSORRIGHT "\e[1C"
@@ -54,15 +57,25 @@
 #define C_COLOR_BLUE "\e[01;34m"
 #define C_COLOR_NORMAL "\e[0m"
 
-static char getch(void)
+#define NON_BLOCKING 1
+
+
+//
+// Get a character code from the keyboard
+//
+static inline int getch(bool nonBlocking)
 {
-    char buf = 0;
+    int buf = 0;
     // old terminal
     struct termios old = {0};
 
     // force flush stdout
     fflush(stdout);
 
+    // Set non-blocking mode if asked
+    if(nonBlocking)
+        fcntl(0, F_SETFL, O_NONBLOCK);
+
     if(tcgetattr(0, &old) < 0) {
         printLog("%sError getting terminal settings! (%s)\n",
                  C_COLOR_RED,
@@ -72,8 +85,6 @@ static char getch(void)
 
     old.c_lflag &= ~ICANON; // disable buffered I/O
     old.c_lflag &= ~ECHO;   // set no echo mode
-    old.c_cc[VMIN] = 1;
-    old.c_cc[VTIME] = 0;
 
     if(tcsetattr(0, TCSANOW, &old) < 0) {
         printLog("%sError setting terminal settings! (%s)\n",
@@ -82,7 +93,12 @@ static char getch(void)
         return -1;
     }
 
-    if(read(0, &buf, 1) < 0) {
+    buf = getchar();
+    if(buf < 0) {
+        // Check target busy (try again)
+        if(errno == EAGAIN)
+            return 0;
+
         printLog("%sError reading character! (%s)\n",
                  C_COLOR_RED,
                  strerror(errno));
@@ -98,11 +114,120 @@ static char getch(void)
                  strerror(errno));
         return -1;
     }
+
+    // Reset blocking mode
+    if(nonBlocking)
+        fcntl(0, F_SETFL, 0);
+
     return buf;
  }
 
+ //
+ // Decorations
+ //
+ void decorateMonitor(struct winsize *terminalSize)
+{
+    printf(C_CLEARSCREEN "\n");
 
-void connectedCommunication(int sockfd)
+    // print decorations
+    for (int i = 0; i < terminalSize->ws_col; i++) {
+        printf("*");
+    }
+
+    for (int i = 0;
+         i < (terminalSize->ws_row-2) * terminalSize->ws_col;
+         i++) {
+        if ((i % terminalSize->ws_col == 0) ||
+            (i % terminalSize->ws_col == terminalSize->ws_col - 1))
+            printf("|");
+        else
+            printf(" ");
+    }
+
+    for (int i = 0; i < terminalSize->ws_col; i++) {
+        printf("*");
+    }
+
+    fflush(stdout);
+}
+
+
+//
+// Monitor mode main loop
+//
+int connectedMonitor(int sockfd)
+{
+    char sendBuff[SEND_BUFFER_SIZE] = {0};
+    char receiveBuff[RECEIVE_BUFFER_SIZE] = {0};
+
+    int pleaseStop = 0;
+
+    char curChar;
+    int answerLength;
+
+    struct winsize terminalSize, oldTerminalSize;
+
+    // Get current terminal size
+    ioctl(STDOUT_FILENO, TIOCGWINSZ, &terminalSize);
+    memcpy(&oldTerminalSize, &terminalSize, sizeof(struct winsize));
+
+    decorateMonitor(&terminalSize);
+
+
+    while (!pleaseStop) {
+        // Zeroing buffer
+        bzero(sendBuff, sizeof(sendBuff));
+
+
+        // Get current terminal size and redecorate if it has changed
+        ioctl(STDOUT_FILENO, TIOCGWINSZ, &terminalSize);
+        if (terminalSize.ws_row != oldTerminalSize.ws_row ||
+            terminalSize.ws_col != oldTerminalSize.ws_col
+            ) {
+            memcpy(&oldTerminalSize, &terminalSize, sizeof(struct winsize));
+            decorateMonitor(&terminalSize);
+        }
+
+        // Read command from terminal
+        curChar = getch(NON_BLOCKING);
+
+        if (curChar > 0) {
+            printLog("Char detected : %d\n", curChar);
+        }
+
+        switch (curChar) {
+        case 'q':
+            pleaseStop = true;
+            break;
+
+        }
+
+        /* // Otherwise send command to server */
+        /* send(sockfd, sendBuff, sizeof(sendBuff), 0); */
+
+        /* // Zeroing buffer */
+        /* bzero(receiveBuff, sizeof(receiveBuff)); */
+
+        /* // Reading server answer */
+        /* answerLength = recv(sockfd, receiveBuff, sizeof(receiveBuff), 0); */
+
+        /* // Detect disconnection */
+        /* if (answerLength == 0) { */
+        /*     break; */
+        /* } */
+
+        /* // Detect null-string returned */
+        /* if (receiveBuff[0] == '\0') { */
+        /*     // Invalid command */
+        /* } */
+    }
+    printf("%sEnd of monitoring session\n\e[0m", C_COLOR_YELLOW);
+}
+
+//
+// Main CLI loop
+//
+void connectedCommandLine(int sockfd)
 {
     char sendBuff[SEND_BUFFER_SIZE] = {0};
     char receiveBuff[RECEIVE_BUFFER_SIZE] = {0};
@@ -113,8 +238,9 @@ void connectedCommunication(int sockfd)
     char curChar;
     int curLineLength, curPosition, continueReadLine, answerLength;
 
-    char *exitCommand = "exit";
+    const char *exitCommand = "exit";
-    char *promptString = C_COLOR_BLUE "gem-graph console" C_COLOR_NORMAL "> ";
+    const char *monitorCommand = "monitor";
+    const char *promptString = C_COLOR_BLUE "gem-graph console" C_COLOR_NORMAL "> ";
 
     for (;;) {
         // Zeroing buffer
@@ -126,7 +252,7 @@ void connectedCommunication(int sockfd)
         curPosition = 0;
         continueReadLine = 1;
         historyModifier = -1;
-        while (continueReadLine && (curChar = getch())) {
+        while (continueReadLine && (curChar = getch(0))) {
 
             switch (curChar) {
 
@@ -164,9 +290,9 @@ void connectedCommunication(int sockfd)
                 break;
 
             case KEY_ESCAPE:
-                if (getch() == KEY_DIRECTIONS) {
+                if (getch(0) == KEY_DIRECTIONS) {
 
-                    switch(getch()) {
+                    switch(getch(0)) {
 
                     case KEY_ARROW_UP:
                         if (historyIndex <= 0)
@@ -228,7 +354,7 @@ void connectedCommunication(int sockfd)
                 break;
 
             default:
-                if (curLineLength < SEND_BUFFER_SIZE) {
+                if (curLineLength < SEND_BUFFER_SIZE && curChar > 0) {
                     printf("%s", C_SAVE_CURSORPOS);
 
                     memmove(sendBuff + curPosition + 1, sendBuff + curPosition,
@@ -266,6 +392,12 @@ void connectedCommunication(int sockfd)
             break;
         }
 
+        // Launch monitor mode if asked
+        if (strcmp(monitorCommand, sendBuff) == 0) {
+            connectedMonitor(sockfd);
+            continue;
+        }
+
         // Otherwise send command to server
         send(sockfd, sendBuff, sizeof(sendBuff), 0);
 
@@ -290,6 +422,9 @@ void connectedCommunication(int sockfd)
     printf("%sDisconnected\n\e[0m", C_COLOR_YELLOW);
 }
 
+//
+// main
+//
 int main(void)
 {
     int sockfd;
@@ -321,7 +456,7 @@ int main(void)
 
     printLog("%sConnected to server!\n\n", C_COLOR_GREEN);
 
-    connectedCommunication(sockfd);
+    connectedCommandLine(sockfd);
 
     // close the socket
     close(sockfd);