Fill in dummy parse target code

.. but don't actually parse anything yet.  But hey - now it tells you
how many samples it (hasn't) parsed.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parse.c

@@ -4,6 +4,128 @@
 #include <libxml/parser.h>
 #include <libxml/tree.h>
 
+/*
+ * Some silly typedefs to make our units very explicit.
+ *
+ * Also, the units are chosen so that values can be expressible as
+ * integers, so that we never have FP rounding issues. And they
+ * are small enough that converting to/from imperial units doesn't
+ * really matter.
+ *
+ * We also strive to make '0' a meaningless number saying "not
+ * initialized", since many values are things that may not have
+ * been reported (eg tank pressure or temperature from dive
+ * computers that don't support them). But sometimes -1 is an even
+ * more explicit way of saying "not there".
+ *
+ * Thus "millibar" for pressure, for example, or "millikelvin" for
+ * temperatures. Doing temperatures in celsius or fahrenheit would
+ * make for loss of precision when converting from one to the other,
+ * and using millikelvin is SI-like but also means that a temperature
+ * of '0' is clearly just a missing temperature or tank pressure.
+ *
+ * Also strive to use units that can not possibly be mistaken for a
+ * valid value in a "normal" system without conversion. If the max
+ * depth of a dive is '20000', you probably didn't convert from mm on
+ * output, or if the max depth gets reported as "0.2ft" it was either
+ * a really boring dive, or there was some missing input conversion,
+ * and a 60-ft dive got recorded as 60mm.
+ *
+ * Doing these as "structs containing value" means that we always
+ * have to explicitly write out those units in order to get at the
+ * actual value. So there is hopefully little fear of using a value
+ * in millikelvin as Fahrenheit by mistake.
+ *
+ * We don't actually use these all yet, so maybe they'll change, but
+ * I made a number of types as guidelines.
+ */
+typedef struct {
+	int seconds;
+} duration_t;
+
+typedef struct {
+	int mm;
+} depth_t;
+
+typedef struct {
+	int mbar;
+} pressure_t;
+
+typedef struct {
+	int mkelvin;
+} temperature_t;
+
+typedef struct {
+	int mliter;
+} volume_t;
+
+typedef struct {
+	int permille;
+} fraction_t;
+
+typedef struct {
+	int grams;
+} weight_t;
+
+typedef struct {
+	fraction_t o2;
+	fraction_t n2;
+	fraction_t he2;
+} gasmix_t;
+
+typedef struct {
+	volume_t size;
+	pressure_t pressure;
+} tank_type_t;
+
+struct sample {
+	duration_t time;
+	depth_t depth;
+	temperature_t temperature;
+	pressure_t tankpressure;
+	int tankindex;
+};
+
+struct dive {
+	time_t when;
+	depth_t maxdepth, meandepth;
+	duration_t duration, surfacetime;
+	depth_t visibility;
+	temperature_t airtemp, watertemp;
+	pressure_t beginning_pressure, end_pressure;
+	int samples;
+	struct sample sample[];
+};
+
+static void record_dive(struct dive *dive)
+{
+	static int nr;
+
+	printf("Recording dive %d with %d samples\n", ++nr, dive->samples);
+}
+
+/* We're in samples - try to convert the random xml value to something useful */
+static void try_to_fill_sample(struct sample *sample, const char *name, int size, const char *buffer)
+{
+}
+
+/* We're in the top-level dive xml. Try to convert whatever value to a dive value */
+static void try_to_fill_dive(struct dive *dive, const char *name, int size, const char *buffer)
+{
+}
+
+/*
+ * Dive info as it is being built up..
+ */
+static int alloc_samples;
+static struct dive *dive;
+static struct sample *sample;
+
+static unsigned int dive_size(int samples)
+{
+	return sizeof(struct dive) + samples*sizeof(struct sample);
+}
+
 /*
  * File boundaries are dive boundaries. But sometimes there are
  * multiple dives per file, so there can be other events too that
@@ -12,25 +134,61 @@
  */
 static void dive_start(void)
 {
-	printf("---\n");
+	unsigned int size;
+
+	alloc_samples = 5;
+	size = dive_size(alloc_samples);
+	dive = malloc(size);
+	if (!dive)
+		exit(1);
+	memset(dive, 0, size);
 }
 
 static void dive_end(void)
 {
+	if (!dive)
+		return;
+	record_dive(dive);
+	dive = NULL;
 }
 
 static void sample_start(void)
 {
-	printf("Sample:\n");
+	int nr;
+
+	if (!dive)
+		return;
+	nr = dive->samples;
+	if (nr >= alloc_samples) {
+		unsigned int size;
+
+		alloc_samples = (alloc_samples * 3)/2 + 10;
+		size = dive_size(alloc_samples);
+		dive = realloc(dive, size);
+		if (!dive)
+			return;
+	}
+	sample = dive->samples + nr;
 }
 
 static void sample_end(void)
 {
+	sample = NULL;
+	if (!dive)
+		return;
+	dive->samples++;
 }
 
 static void entry(const char *name, int size, const char *buffer)
 {
-	printf("%s: %.*s\n", name, size, buffer);
+	if (sample) {
+		try_to_fill_sample(sample, name, size, buffer);
+		return;
+	}
+	if (dive) {
+		try_to_fill_dive(dive, name, size, buffer);
+		return;
+	}
 }
 
 static const char *nodename(xmlNode *node, char *buf, int len)