Added bunch of examples

1 files changed, 194 insertions, 0 deletions

diff --git a/portmidi/pm_test/sendvirtual.c b/portmidi/pm_test/sendvirtual.c
new file mode 100644
index 0000000..a60a48f
--- /dev/null
+++ b/portmidi/pm_test/sendvirtual.c
@@ -0,0 +1,194 @@
+/* sendvirtual.c -- test for creating a virtual device and sending to it */
+/*
+ * Roger B. Dannenberg
+ * Sep 2021
+ */
+#include "portmidi.h"
+#include "porttime.h"
+#include "stdlib.h"
+#include "stdio.h"
+#include "string.h"
+#include "assert.h"
+
+#define OUTPUT_BUFFER_SIZE 0
+#define TIME_PROC ((PmTimeProcPtr) Pt_Time)
+#define TIME_INFO NULL
+#define TIME_START Pt_Start(1, 0, 0) /* timer started w/millisecond accuracy */
+
+int latency = 0;
+PmSysDepInfo *sysdepinfo = NULL;
+char *port_name = "portmidi";
+
+static void set_sysdepinfo(char m_or_p, const char *name)
+{
+    if (!sysdepinfo) {
+        // allocate some space we will alias with open-ended PmDriverInfo:
+        // there is space for 4 parameters:
+        static char dimem[sizeof(PmSysDepInfo) + sizeof(void *) * 8];
+        sysdepinfo = (PmSysDepInfo *) dimem;
+        // build the driver info structure:
+        sysdepinfo->structVersion = PM_SYSDEPINFO_VERS;
+        sysdepinfo->length = 0;
+    }
+    if (sysdepinfo->length > 1) {
+        printf("Error: sysdepinfo was allocated to hold 2 parameters\n");
+        exit(1);
+    }
+    int i = sysdepinfo->length++;
+    enum PmSysDepPropertyKey k = pmKeyNone;
+    if (m_or_p == 'm') k = pmKeyCoreMidiManufacturer;
+    else if (m_or_p == 'p') k = pmKeyAlsaPortName;
+    else if (m_or_p == 'c') k = pmKeyAlsaClientName;
+    sysdepinfo->properties[i].key = k;
+    sysdepinfo->properties[i].value = name;
+}
+
+
+static void prompt_and_exit(void)
+{
+    printf("type ENTER...");
+    while (getchar() != '\n') ;
+    /* this will clean up open ports: */
+    exit(-1);
+}
+
+
+static PmError checkerror(PmError err)
+{
+    if (err == pmHostError) {
+        /* it seems pointless to allocate memory and copy the string,
+         * so I will do the work of Pm_GetHostErrorText directly
+         */
+        char errmsg[80];
+        Pm_GetHostErrorText(errmsg, 80);
+        printf("PortMidi found host error...\n  %s\n", errmsg);
+        prompt_and_exit();
+    } else if (err < 0) {
+        printf("PortMidi call failed...\n  %s\n", Pm_GetErrorText(err));
+        prompt_and_exit();
+    }
+    return err;
+}
+
+
+void wait_until(PmTimestamp when)
+{
+    PtTimestamp now = Pt_Time();
+    if (when > now) {
+        Pt_Sleep(when - now);
+    }
+}
+
+
+void main_test_output(int num)
+{
+    PmStream *midi;
+    int32_t next_time;
+    PmEvent buffer[1];
+    PmTimestamp timestamp;
+    int pitch = 60;
+    int id;
+
+    /* It is recommended to start timer before Midi; otherwise, PortMidi may
+       start the timer with its (default) parameters
+     */
+    TIME_START;
+
+    /* create a virtual output device */
+    id = checkerror(Pm_CreateVirtualOutput(port_name, NULL, sysdepinfo));
+    checkerror(Pm_OpenOutput(&midi, id, sysdepinfo, OUTPUT_BUFFER_SIZE,
+                             TIME_PROC, TIME_INFO, latency));
+
+    printf("Midi Output Virtual Device \"%s\" created.\n", port_name);
+    printf("Type ENTER to send messages: ");
+    while (getchar() != '\n') ;
+
+    buffer[0].timestamp = Pt_Time();
+#define PROGRAM 0
+    buffer[0].message = Pm_Message(0xC0, PROGRAM, 0);
+    Pm_Write(midi, buffer, 1);
+    next_time = Pt_Time() + 1000;  /* wait 1s */
+    while (num > 0) {
+        wait_until(next_time);
+        Pm_WriteShort(midi, next_time, Pm_Message(0x90, pitch, 100));
+        printf("Note On pitch %d\n", pitch);
+        num--;
+        next_time += 500;
+
+        wait_until(next_time);
+        Pm_WriteShort(midi, next_time, Pm_Message(0x90, pitch, 0));
+        printf("Note Off pitch %d\n", pitch);
+        num--;
+        pitch = (pitch + 1) % 12 + 60;
+        next_time += 500;
+    }
+
+    /* close device (this not explicitly needed in most implementations) */
+    printf("ready to close...");
+    Pm_Close(midi);
+    printf("done closing.\nNow delete the virtual device...");
+    checkerror(Pm_DeleteVirtualDevice(id));
+    printf("done deleting.\n");
+}
+
+
+void show_usage()
+{
+    printf("Usage: sendvirtual [-h] [-l latency-in-ms] [-m manufacturer] "
+           "[-c clientname] [-p portname] [n]\n"
+           "    -h for this message,\n"
+           "    -l ms designates latency for precise timing (default 0),\n"
+           "    -m name designates a manufacturer name (macOS only),\n"
+           "    -c name designates a client name (linux only),\n"
+           "    -p name designates a port name (linux only),\n"
+           "    n is number of message to send.\n"
+           "sends change program to 1, then one note per second with 0.5s on,\n"
+           "0.5s off, for n/2 seconds. Latency >0 uses the device driver for \n"
+           "precise timing (see PortMidi documentation).\n"); 
+    exit(0);
+}
+
+
+int main(int argc, char *argv[])
+{
+    int num = 10;
+    int i;
+    if (argc <= 1) {
+        show_usage();
+    }
+    for (i = 1; i < argc; i++) {
+        if (strcmp(argv[i], "-h") == 0) {
+            show_usage();
+        } else if (strcmp(argv[i], "-l") == 0 && (i + 1 < argc)) {
+            i = i + 1;
+            latency = atoi(argv[i]);
+            printf("Latency will be %d\n", latency);
+        } else if (strcmp(argv[i], "-m") == 0 && (i + 1 < argc)) {
+            i = i + 1;
+            set_sysdepinfo('m', argv[i]);
+            printf("Manufacturer name will be %s\n", argv[i]);
+        } else if (strcmp(argv[i], "-p") == 0 && (i + 1 < argc)) {
+            i = i + 1;
+            port_name = argv[i];
+            set_sysdepinfo('p', port_name);
+            printf("Port name will be %s\n", port_name);
+        } else if (strcmp(argv[i], "-c") == 0 && (i + 1 < argc)) {
+            i = i + 1;
+            set_sysdepinfo('c', argv[i]);
+            printf("Client name will be %s\n", argv[i]);
+        } else {
+            num = atoi(argv[i]);
+            if (num <= 0) {
+                printf("Zero value or non-number for n\n");
+                show_usage();
+            }
+            printf("Sending %d messages.\n", num);
+        }
+    }
+
+    main_test_output(num);
+    
+    printf("finished sendvirtual test...type ENTER to quit...");
+    while (getchar() != '\n') ;
+    return 0;
+}