fix: crash when too many elements in delayed output (as slurs)

The size of the temporary buffer used for delayed output was not correct.
Now, this buffer is allocated from the heap with the same size as the
output normal buffer.

Issue #16.

abcm2ps.h

@@ -559,6 +559,7 @@ typedef struct SYMBOL *INFO[26]; /* information fields ('A' .. 'Z') */
 extern INFO info;
 
 extern char *outbuf;		/* output buffer.. should hold one tune */
+extern int outbufsz;		/* size of outbuf */
 extern char *mbf;		/* where to PUTx() */
 extern int use_buffer;		/* 1 if lines are being accumulated */
 

buffer.c

@@ -36,7 +36,7 @@ static float remy;		/* remaining vertical space in page */
 static float bposy;		/* current position in buffered data */
 static int nepsf;		/* counter for -E/-g output files */
 static int nbpages;		/* number of pages in the output file */
-static int outbufsz;		/* size of outbuf */
+	int outbufsz;		/* size of outbuf */
 static char outfnam[FILENAME_MAX]; /* internal file name for open/close */
 static struct FORMAT *p_fmt;	/* current format while treating a new page */
 

music.c

@@ -13,6 +13,7 @@
  */
 
 #include <string.h>
+#include <stdlib.h>
 #include <ctype.h>
 
 #include "abcm2ps.h"
@@ -5068,10 +5069,15 @@ static void error_show(void)
 static float delayed_output(float indent)
 {
 	float line_height;
-	char *outbuf_sav, *mbf_sav, tmpbuf[20 * 1024];
+	char *outbuf_sav, *mbf_sav, *tmpbuf;
 
 	outbuf_sav = outbuf;
 	mbf_sav = mbf;
+	tmpbuf = malloc(outbufsz);
+	if (!tmpbuf) {
+		error(1, NULL, "Out of memory for delayed outbuf - abort");
+		exit(EXIT_FAILURE);
+	}
 	mbf = outbuf = tmpbuf;
 	*outbuf = '\0';
 	outft = -1;
@@ -5081,6 +5087,7 @@ static float delayed_output(float indent)
 	outft = -1;
 	line_height = draw_systems(indent);
 	a2b("%s", tmpbuf);
+	free(tmpbuf);
 	return line_height;
 }