16c7952648
This can happen, e.g., if there is an IO error or if there is insufficient free disk space to flush the data. In this case, fclose should return -1 to report an error, but it should still effectively close the stream and deallocate the buffer for it. (This behavior is explicitly specified in the C99 and later standards.)
Previously, ORCA/C effectively left the stream open in these cases. As a result, the buffer was not deallocated. More importantly, this could cause the program to hang at exit, because the stream would never be removed from the list of open files.
Here is an example program that demonstrates the problem:
/*
* Run this on a volume with less than 1MB of free space, e.g. a floppy.
* The fclose return value should be -1 (EOF), indicating an error, but
* the two RealFreeMem values should be close to each other (indicating
* that the buffer was freed), and the program should not hang on exit.
*/
#include <stdio.h>
#include <stddef.h>
#include <memory.h>
#define BUFFER_SIZE 1000000
int main(void) {
size_t i;
int ret;
printf("At start, RealFreeMem = %lu\n", RealFreeMem());
FILE *f = fopen("testfile", "wb");
if (!f)
return 0;
setvbuf(f, NULL, _IOFBF, BUFFER_SIZE);
for (i = 0; i < BUFFER_SIZE; i++) {
putc('x', f);
}
ret = fclose(f);
printf("fclose return value = %d\n", ret);
printf("At end, RealFreeMem = %lu (should be close to start value)\n",
RealFreeMem());
}
ORCALib
Libraries for the ORCA language suite (ORCA/C, ORCA/M, ORCA/Pascal) for the Apple IIGS
If you would like to make changes to this compiler and distribute them to others, feel free to submit them here. If the changes apply to the Apple IIGS, they will generally be approved for distribution on the master branch. For changes that retarget the library to generate code for a different platform, the project will either be forked or a new repository will be created, as appropriate.
The general conditions that must be met before a change is released on master are:
-
The modified library must compile under the currently released version of ORCA/M.
-
The various languages that make use of the library mush still pass their respective test suites, or changes to those test suites must also be submitted.
Contact support@byteworks.us if you need contributor access.
A complete distribution of the ORCA languages, including installers and documentation, is available from the Juiced GS store at https://juiced.gs/store/category/software/. It is distributed as part of the Opus ][ package.