Diff: circular_buffer.cpp

Revision:

0:2c2b17c7b7a8

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/circular_buffer.cpp	Mon Jan 30 14:53:23 2012 +0000
@@ -0,0 +1,105 @@
+#include    "circular_buffer.h"
+#include    "mbed.h"
+
+using namespace std;
+
+bool    circular_buffer_f::seek    (int distance_back) {   // Assumes at least that much has been written to buff beforehand
+    if(!seek_enable)    return  false;
+    if(buffsize <= distance_back)    return  false;
+    Offbuff = Onbuff - distance_back;       //  Setup to enable read of most recent 'distance_back' samples
+    if(Offbuff < buffbase)  Offbuff += buffsize;
+    emptyf = false;
+    return  true;
+}
+void    circular_buffer_f::init    (int size, float *buffstart, int flags)  {  // Size and address of buffer to work with
+    buffsize = size;
+    Onbuff = Offbuff = buffend = buffbase = buffstart;
+    buffend += (size - 1);
+    emptyf = true; fullf = false;
+    if  (flags & OVERWRITE_ENABLE)  overwrite_enable = true;
+    else overwrite_enable = false;
+    if  (flags & SEEK_ENABLE)       seek_enable = true;
+    else seek_enable = false;
+}
+bool    circular_buffer_f::read (float *rd)  {
+    if(!readable())             return false;
+    *rd = *Offbuff++;
+    if(Offbuff > buffend)       Offbuff = buffbase;
+    if(Onbuff == Offbuff)       emptyf = true;
+    fullf = false;
+    return true;
+}
+bool    circular_buffer_f::write   (float a)  {     // Put value into circular buffer
+    if  (overwrite_enable)  {
+        *Onbuff++ = a;                  // post increment pointer
+        if(Onbuff > buffend)        Onbuff = buffbase;
+        fullf = false;
+    }
+    else    {
+        if(fullf)                   return false;  // Fail if buffer already full
+        *Onbuff++ = a;                  // post increment pointer
+        if(Onbuff > buffend)        Onbuff = buffbase;
+        if(Onbuff == Offbuff)       fullf = true;
+    }
+    emptyf = false;
+    return true;
+}
+bool circular_buffer_f::get_samps (float *dest, int len) {
+    for (int i = 0; i < len; i++)   {
+        if (!read(dest++))
+            return false;
+    }
+    return  true;
+}
+
+//////////////////////////
+
+bool    circular_buffer_c::seek    (int distance_back) {   // Assumes at least that much has been written to buff beforehand
+    if(!seek_enable)    return  false;
+    if(buffsize <= distance_back)    return  false;
+    Offbuff = Onbuff - distance_back;       //  Setup to enable read of most recent 'distance_back' samples
+    if(Offbuff < buffbase)  Offbuff += buffsize;
+    emptyf = false;
+    return  true;
+}
+void    circular_buffer_c::init    (int size, char *buffstart, int flags)  {  // Size and address of buffer to work with
+    buffsize = size;
+    Onbuff = Offbuff = buffend = buffbase = buffstart;
+    buffend += (size - 1);
+    emptyf = true; fullf = false;
+    if  (flags & OVERWRITE_ENABLE)  overwrite_enable = true;
+    else overwrite_enable = false;
+    if  (flags & SEEK_ENABLE)       seek_enable = true;
+    else seek_enable = false;
+}
+bool    circular_buffer_c::read (char *rd)  {
+    if(!readable())             return false;
+    *rd = *Offbuff++;
+    if(Offbuff > buffend)       Offbuff = buffbase;
+    if(Onbuff == Offbuff)       emptyf = true;
+    fullf = false;
+    return true;
+}
+bool    circular_buffer_c::write   (char a)  {     // Put value into circular buffer
+    if  (overwrite_enable)  {
+        *Onbuff++ = a;                  // post increment pointer
+        if(Onbuff > buffend)        Onbuff = buffbase;
+        fullf = false;
+    }
+    else    {
+        if(fullf)                   return false;  // Fail if buffer already full
+        *Onbuff++ = a;                  // post increment pointer
+        if(Onbuff > buffend)        Onbuff = buffbase;
+        if(Onbuff == Offbuff)       fullf = true;
+    }
+    emptyf = false;
+    return true;
+}
+bool circular_buffer_c::get_samps (char *dest, int len) {
+    for (int i = 0; i < len; i++)   {
+        if (!read(dest++))
+            return false;
+    }
+    return  true;
+}
+