From d6a6d80d6e1315d753c9452ad6ad1bc78d51933e Mon Sep 17 00:00:00 2001
From: Matt Jenkins <matt@majenko.co.uk>
Date: Tue, 29 Apr 2014 17:31:37 +0100
Subject: [PATCH] Fixed parsing of partition data

The previous method of parsing the prepartition data didn't work right
when you had more than one device.  The new version first finds the
device entry and then parses the partitions from that point on.
---
 sys/kernel/rdisk.c | 176 +++++++++++++++++++++++++--------------------
 1 file changed, 98 insertions(+), 78 deletions(-)

diff --git a/sys/kernel/rdisk.c b/sys/kernel/rdisk.c
index dea62b0..825b81b 100644
--- a/sys/kernel/rdisk.c
+++ b/sys/kernel/rdisk.c
@@ -69,10 +69,14 @@ const struct diskentry disks[] = {
 	{sd_preinit, sdinit, sddeinit, sdopen, sdsize, card_read, card_write, 1, RD_DEFAULT},
 #endif
 
-#ifdef SRAMC_ENABLED
+#ifdef SRAMC0_ENABLED
 	{sramc_init, no_init, no_deinit, sramc_open, sramc_size, sramc_read, sramc_write, 0, RD_PREPART},
 #endif
 
+#ifdef SRAMC1_ENABLED
+	{sramc_init, no_init, no_deinit, sramc_open, sramc_size, sramc_read, sramc_write, 1, RD_PREPART},
+#endif
+
 #ifdef SDRAMP_ENABLED
 	{sdramp_preinit, no_init, no_deinit, sdramp_open, sdramp_size, sdramp_read, sdramp_write, 0, RD_PREPART},
 #endif	
@@ -576,100 +580,116 @@ struct buf *prepartition_device(char *devname)
 	int pnum = 0;
 	int start = 2;
 	char dev[9];
-	char size[9];
-	char type[5];
-	int pos = 0;
+	int size;
+    int devsize = 0;
+    char *ptdata = NULL;
 
-	p = prepartition_schema+1;
-	q = p;
+    char *ppstart = prepartition_schema;
+
+    while (*ppstart == '(') {
+        ppstart++;
+    }
 
 	printf("PP Schema: %s\n",prepartition_schema);
 
+    printf("Attempting partition of %s...\n", devname);
+
+    // Let's get the devname into the "dev" variable and append a ":" on the end of it.
+    q = dev;
+    for (p=devname; *p; p++) {
+        *q = *p;
+        q++;
+        devsize++;
+    }
+    *q++ = ':';
+    *q = 0;
+    devsize++;
+
+    printf("%%DBG-PPT: Device Name: %s (%d chars)\n", dev, devsize);
+
+    // Now we want to scan the string to find the device name.  It has to either
+    // be at the start of the string or be prefixed by a ' '
+    for (p = ppstart; *(p+devsize); p++) {
+        if (strncmp(p, dev, devsize) == 0) {
+            printf("%%DBG-PPT: Device found.\n");
+            ptdata = p + devsize;
+            break;
+        }
+    }
+    if (ptdata == NULL) {
+        printf("%%DBG-PPT: Device not in partition schema\n");
+        return NULL;
+    }
+    
+
+    // We must have a pointer to the start of the partition data in ptdata now.
+    // Now to scan through it and get the data into the structures.
+        
+    printf("%%DBG-PPT: We now like this bit: %s\n", ptdata);
+    
 	bp = getnewbuf();
-	if(!bp)
-	{
+	if(!bp) {
+        printf("%%DBG-PPT: Unable to allocate buffer!\n");
 		return NULL;
 	}
 
 	mbr = (struct mbr *)bp->b_addr;
 
-	while(*p)
-	{
-		while(*q && *q != ' ')
-			q++;
-		if(*q == ' ')
-		{
-			*q = 0;
-			q++;
-		}
+    // Ok, let's scan through the data one character at a time until we hit either a 
+    // space or a close-bracket (indicating the end of the data).
 
-		pos = 0;
-		while((*p) && (*p != ':'))
-		{
-			dev[pos++] = *p;
-			dev[pos] = 0;
-			p++;
-		}
-	
-		if((*p) == ':')
-		{
-			p++;
-		} else {
-			printf("Device Format Error (%c)\n",*p);
-			brelse(bp);
-			return NULL;
-		}
+    p = ptdata;
+    pnum = 0;
+    while ((*p != ' ') && (*p != ')')) {
+        // First let's look to see if we have a valid partition type - it's 2 characters
+        // followed by an '@'.
 
-		while((*p) && (*p != ' '))
-		{
-			pos = 0;
-			while((*p) && (*p != '@'))
-			{
-				type[pos++] = *p;
-				type[pos] = 0;
-				p++;
-			}
+        printf("%%DBG-PPT: Looking at: %s\n", p);
 
-			if((*p) == '@')
-			{
-				p++;
-			} else {
-				printf("Type Format Error\n");
-				brelse(bp);
-				return NULL;
-			}
+        // Active swap space
+        if (strncmp(p, "sa@", 3) == 0) {
+            mbr->partitions[pnum].type=RDISK_SWAP;
+            mbr->partitions[pnum].status = 0x80;
+        } else
 
-			pos = 0;
-			while((*p) && (*p != ',') && (*p != ' ') && (*p != ')'))
-			{
-				size[pos++] = *p;
-				size[pos] = 0;
-				p++;
-			}
+        // Inactive swap space
+        if (strncmp(p, "sw@", 3) == 0) {
+            mbr->partitions[pnum].type=RDISK_SWAP;
+        } else
 
-			printf("Found partition on %s of type %s and size %s\n",
-				dev,type,size);
+        // General UFS filesystem
+        if (strncmp(p, "fs@", 3) == 0) {
+            mbr->partitions[pnum].type=RDISK_FS;
+        } else {
+            printf("%%DBG-PPT: Error parsing partition data: %s\n", p);
+            brelse(bp);
+            return NULL;
+        }
 
-			if(!strcmp(dev,devname))
-			{
-				if(!strcmp("sw",type))
-					mbr->partitions[pnum].type=RDISK_SWAP;
-				if(!strcmp("sa",type))
-				{
-					mbr->partitions[pnum].type=RDISK_SWAP;
-					mbr->partitions[pnum].status = 0x80;
-				}
-				if(!strcmp("fs",type))
-					mbr->partitions[pnum].type=RDISK_FS;
+        p+=3;
 
-				mbr->partitions[pnum].lbastart = start;
-				mbr->partitions[pnum].lbalength = atoi(size)<<1;
-				start += mbr->partitions[pnum].lbalength;
-				pnum++;
-			}
-			p++;
-		}
-	}
+        size = 0;
+        while ((*p >= '0') && (*p <= '9')) {
+            size *= 10;
+            size += *p - '0';
+            p++;
+        }
+
+        mbr->partitions[pnum].lbastart = start;
+        mbr->partitions[pnum].lbalength = size << 1;
+
+        printf("%%DBG-PPT: Added partition %d type %d size %d at offset %d\n", 
+            pnum,
+            mbr->partitions[pnum].type,
+            mbr->partitions[pnum].lbalength,
+            mbr->partitions[pnum].lbastart
+        );
+        start += (size << 1);
+        pnum++;
+        if (*p == ',') {
+            p++;
+        }
+    }
 	
 	if(pnum > 0)
 	{