izaya/collapseos
1
0
Fork 0
mirror of https://github.com/hsoft/collapseos.git synced 2025-04-04 13:38:39 +11:00
Code Issues Releases Wiki Activity

Fix filesystem in shell emulator

Browse Source 
We now treat the block device as fixed-size rather than trying to grow it in response
to kernel activity.

Previously, if you tried to create 2 files in a row, only the first 1 would actually appear,
because the device only ever got larger when a byte was written immediately past the end of
the device.

Now we just let the kernel write bytes to the disk anywhere, so new files can be created even
when the previous file is not completely full.

Also, fix buffer overrun in reading filesystem image, and use a more idiomatic fgetc loop.
This commit is contained in:
James Stanley 2019-10-16 19:55:12 +01:00
parent 5460f28cfb
commit 909da5177f
1 changed files with 11 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

33
tools/emul/shell/shell.c
View File

@ -42,7 +42,6 @@
static Z80Context cpu;
static uint8_t mem[0x10000] = {0};
static uint8_t fsdev[MAX_FSDEV_SIZE] = {0};
static uint32_t fsdev_size = 0;
static uint32_t fsdev_ptr = 0;
// 0 = idle, 1 = received MSB (of 24bit addr), 2 = received middle addr
static int fsdev_addr_lvl = 0;
@ -62,14 +61,13 @@ static uint8_t io_read(int unused, uint16_t addr)
fprintf(stderr, "Reading FSDEV in the middle of an addr op (%d)\n", fsdev_ptr);
return 0;
}
if (fsdev_ptr < fsdev_size) {
if (fsdev_ptr < MAX_FSDEV_SIZE) {
#ifdef DEBUG
fprintf(stderr, "Reading FSDEV at offset %d\n", fsdev_ptr);
#endif
return fsdev[fsdev_ptr];
} else {
// don't warn when ==, we're not out of bounds, just at the edge.
if (fsdev_ptr > fsdev_size) {
if (fsdev_ptr >= MAX_FSDEV_SIZE) {
fprintf(stderr, "Out of bounds FSDEV read at %d\n", fsdev_ptr);
}
return 0;
@ -77,11 +75,8 @@ static uint8_t io_read(int unused, uint16_t addr)
} else if (addr == FS_ADDR_PORT) {
if (fsdev_addr_lvl != 0) {
return 3;
} else if (fsdev_ptr > fsdev_size) {
fprintf(stderr, "Out of bounds FSDEV addr request at %d / %d\n", fsdev_ptr, fsdev_size);
} else if (fsdev_ptr > MAX_FSDEV_SIZE) {
return 2;
} else if (fsdev_ptr == fsdev_size) {
return 1;
} else {
return 0;
}
@ -105,18 +100,11 @@ static void io_write(int unused, uint16_t addr, uint8_t val)
fprintf(stderr, "Writing to FSDEV in the middle of an addr op (%d)\n", fsdev_ptr);
return;
}
if (fsdev_ptr < fsdev_size) {
if (fsdev_ptr < MAX_FSDEV_SIZE) {
#ifdef DEBUG
fprintf(stderr, "Writing to FSDEV (%d)\n", fsdev_ptr);
#endif
fsdev[fsdev_ptr] = val;
} else if ((fsdev_ptr == fsdev_size) && (fsdev_ptr < MAX_FSDEV_SIZE)) {
// We're at the end of fsdev, grow it
fsdev[fsdev_ptr] = val;
fsdev_size++;
#ifdef DEBUG
fprintf(stderr, "Growing FSDEV (%d)\n", fsdev_ptr);
#endif
} else {
fprintf(stderr, "Out of bounds FSDEV write at %d\n", fsdev_ptr);
}
@ -156,13 +144,14 @@ int main()
if (fp != NULL) {
printf("Initializing filesystem\n");
int i = 0;
int c = fgetc(fp);
while (c != EOF) {
fsdev[i] = c & 0xff;
i++;
c = fgetc(fp);
int c;
while ((c = fgetc(fp)) != EOF && i < MAX_FSDEV_SIZE) {
fsdev[i++] = c & 0xff;
}
if (i == MAX_FSDEV_SIZE) {
fprintf(stderr, "Filesytem image too large.\n");
return 1;
}
fsdev_size = i;
pclose(fp);
} else {
printf("Can't initialize filesystem. Leaving blank.\n");