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POHow to read from buffer with feedback, so doesn't buffer overflow?
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copied!<p>I have this code</p> <pre><code>#define BUFFER_LEN (2048) static float buffer[BUFFER_LEN]; int readcount; while ((readcount = sf_read_float(handle, buffer, BUFFER_LEN))) { // alsa play } </code></pre> <p>which reads BUFFER_LEN floats from buffer, and returns the number of floats it actually read. "handle" tells sf_rad_float how big buffer is.</p> <p>E.g. if buffer contains 5 floats, and BUFFER_LEN is 3, readcount would first return 3, and next time 2, and the while-loop would exit.</p> <p>I would like to have a function that does the same.</p> <p><strong>Update</strong></p> <p>After a lot of coding, I think this is the solution.</p> <pre><code>#include <stdio.h> int copy_buffer(double* src, int src_length, int* src_pos, float* dest, int dest_length) { int copy_length = 0; if (src_length - *src_pos > dest_length) { copy_length = dest_length; printf("copy_length1 %i\n", copy_length); } else { copy_length = src_length - *src_pos; printf("copy_length2 %i\n", copy_length); } for (int i = 0; i < copy_length; i++) { dest[i] = (float) src[*src_pos + i]; } // remember where to continue next time the copy_buffer() is called *src_pos += copy_length; return copy_length; } int main() { double src[] = {1,2,3,4,5}; int src_length = 5; float dest[] = {0,0}; int dest_length = 2; int read; int src_pos = 0; read = copy_buffer(src, src_length, &src_pos, dest, dest_length); printf("read %i\n", read); printf("src_pos %i\n", src_pos); for (int i = 0; i < src_length; i++) { printf("src %f\n", src[i]); } for (int i = 0; i < dest_length; i++) { printf("dest %f\n", dest[i]); } return 0; } </code></pre> <p>Next time copy_buffer() is called, dest contains 3,4. Running <code>copy_buffer()</code> again only copies the value "5". So I think it works now.</p> <p>Although it is not very pretty, that I have <code>int src_pos = 0;</code> outside on <code>copy_buffer()</code>.</p> <p>It would be a lot better, if I instead could give <code>copy_buffer()</code> a unique handle instead of <code>&src_pos</code>, just like sndfile does.</p> <p>Does anyone know how that could be done?</p>

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