assplode() routine to help with parsing

git-svn-id: svn://cook.msm.cam.ac.uk:745/thrust3d/thrust3d@4 84d2e878-0bd5-11dd-ad15-13eda11d74c5

3 files changed, 93 insertions, 2 deletions

diff --git a/src/model.c b/src/model.c
index d50159d..40ecde8 100644
--- a/src/model.c
+++ b/src/model.c
@@ -213,13 +213,30 @@ static int model_load_obj(ModelContext *ctx, const char *name, RenderContext *re
 		}
 		
 		if ( line[s] == 'f' ) {
-			
+			char **bits;
+			int i, n;
+			n = assplode(line, " \t\r\n", &bits);
+			printf("The %i bits are:\n", n);
+			for ( i=0; i<n; i++ ) {
+				char **sp;
+				int np, ip;
+				printf("%3i: '%s'\n", i, bits[i]);
+				np = assplode(bits[i], "/", &sp);
+				for ( ip=0; ip<np; ip++ ) {
+					printf("Subbit %i: '%s'\n", ip, sp[ip]);
+				}
+				if ( np < 3 ) {
+					continue;
+				}
+				free(bits[i]);
+			}
+			free(bits);
 		}
 		
 	}
 	
 	fclose(fh);
-
+	
 	return model_add(ctx, model);
 	
 }
diff --git a/src/utils.c b/src/utils.c
index fad8edb..a407416 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -14,6 +14,7 @@
 #endif
 
 #include <string.h>
+#include <stdlib.h>
 
 void chomp(char *a) {
 
@@ -28,3 +29,75 @@ void chomp(char *a) {
 
 }
 
+/* Return non-zero if c is in delims */
+static int assplode_isdelim(const char c, const char *delims) {
+	size_t i;
+	for ( i=0; i<strlen(delims); i++ ) {
+		if ( c == delims[i] ) return 1;
+	}
+	return 0;
+}
+
+static int assplode_extract(char ***pbits, int n, size_t n_captured, size_t start, const char *a) {
+	char **bits = *pbits;
+	bits = realloc(bits, sizeof(char *)*(n+1));
+	bits[n] = malloc(n_captured+1);
+	memcpy(bits[n], a+start, n_captured);
+	bits[n][n_captured] = '\0';
+	n++;
+	*pbits = bits;
+	return n;
+}
+
+/* Split the string 'a' using 'delims' as a zero-terminated list of deliminators.
+ * Store each segment in bits[0...n] where n is the number of segments and is the
+ *  return value.  pbits = &bits
+ * Each segment needs to be freed with free() when finished with.
+ * The array of bits also needs to be freed with free() when finished with, unless
+ *  n=0 in which case bits==NULL
+ */
+int assplode(const char *a, const char *delims, char ***pbits) {
+
+	size_t i, start, n_captured;
+	int n;
+	char **bits;
+	
+	n = 0;
+	i = 0;
+	n_captured = 0;
+	start = 0;
+	bits = NULL;
+	while ( i < strlen(a) ) {
+	
+		if ( assplode_isdelim(a[i], delims) ) {
+			
+			if ( n_captured > 0 ) {
+				/* This is a deliminator after a sequence of non-deliminator chars */
+				n = assplode_extract(&bits, n, n_captured, start, a);
+			}
+			
+			n_captured = 0;
+			
+		} else {
+			
+			if ( n_captured == 0 ) {
+				/* No characters currently found, so this is the start */
+				start = i;
+			}
+			n_captured++;
+			
+		}
+		
+		i++;
+	
+	}
+	/* Left over characters at the end? */
+	if ( n_captured > 0 ) {
+		n = assplode_extract(&bits, n, n_captured, start, a);
+	}
+	
+	*pbits = bits;
+	return n;
+
+}
+
diff --git a/src/utils.h b/src/utils.h
index cfbf6ad..ff34a5f 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -22,6 +22,7 @@
 #define deg2rad(a) ((a)*M_PI/180)
 
 extern void chomp(char *a);
+extern int assplode(const char *a, const char *delims, char ***pbits);
 
 #endif	/* UTILS_H */