std: add streamUntilEof to io #22681
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lib/std/io/Reader.zig
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| ) anyerror!void { | ||
| if (optional_max_size) |max_size| { | ||
| for (0..max_size) |_| { | ||
| const byte: u8 = try self.readByte(); |
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This should use read or readAll for efficiency, see the implementation of readAllArrayListAligned(). There is no need to check every byte as we are not searching for a delimiter here.
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I couldn't really figure out a way to do this while still using the writer pattern. I'm not too sure how important that is?
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Right, the more efficient approach requires a buffer. As mlugg points out in #22677 (comment), the core of this functionality is already provided by LinearFifo.pump(). The part that's missing from pump() is the ability to set a max size for robustness.
In any case, it would be good if streamUntilEof() did not require an allocator, I suppose we might need to make the fixed size of the buffer configurable though, I'm not sure what the ideal interface here is.
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The reason why I wanted this functionality was basically the usecase of 'fill up an ArrayList with the contents of this file' I wanted heap alocated memory specifically because I don't want to have to care about how much space I need to store the file. I've only been using zig for a few weeks so I'm still a bit fresh so apologies if I don't make any sense.
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The reason why I wanted this functionality was basically the usecase of 'fill up an ArrayList with the contents of this file'
This already exists as readAllArrayList (or, if you just want the whole file in a buffer and don't actually need to mutate the arraylist afterwards, readAllAlloc).
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Ah right thanks for that, I got a bit interested in seeing if I could make this work with the fifo.pump that was mentioned. I've managed to pull some of the logic out of that to be able to have a max length while still using the same underlying stuff
In any case, it would be good if streamUntilEof() did not require an allocator, I suppose we might need to make the fixed size of the buffer configurable though, I'm not sure what the ideal interface here is.
@ifreund - I think I've pretty much managed what you're asking here:
It's currently quite inconvenient to read an entire file using the streamUntilDelimiter function, this one replicates most of the same functionality but will read until it hits EOF rather than a delimiter.