Updated to 1.35 but same problem... Maybe the question to formulate would be: How can I save in a global/static variable some information so that I can acces it later in the callback function and make sure it's not overwritten? What do you think about using malloc() somehow? Would it work?
2015-10-20 14:18 GMT-07:00 Alon Zakai <[email protected]>: > Might be worth trying current master (or incoming) then, which is now > 1.35.0. > > On Tue, Oct 20, 2015 at 2:16 PM, Pau Ballart <[email protected]> wrote: > >> $ emcc -v >> emcc (Emscripten gcc/clang-like replacement + linker emulating GNU ld) >> 1.34.8 >> clang version 3.7.0 >> Target: x86_64-apple-darwin15.0.0 >> Thread model: posix >> INFO root: (Emscripten: Running sanity checks) >> >> 2015-10-20 14:05 GMT-07:00 Alon Zakai <[email protected]>: >> >>> One possible issue is that if those values are on the stack, and the >>> scope exits, then that stack memory might be reused. For example this is >>> unsafe: >>> >>> { >>> char buffer[100]; >>> // write into buffer >>> emscripten_async_wget(..., (void*)buffer); >>> } >>> >>> The buffer will be released before the async callback occurs, and other >>> data might be written into it before the callback reads from it. >>> >>> Which version of emscripten are you using, btw? I remember a while back >>> we had a bug around this. >>> >>> On Tue, Oct 20, 2015 at 1:36 PM, Pau Ballart <[email protected]> wrote: >>> >>>> Hello, >>>> >>>> After some research and some refactor I did the following: >>>> >>>> - In my p3stuff function I >>>> call emscripten_set_main_loop(wait_wgets, 0, 0); so the application is >>>> not >>>> terminated. >>>> - In wait_wgets I call the emscripten_async_wget(imageUrl, path, >>>> onLoaded, onError); only the first time the method is called. >>>> - In the onLoaded callback I call emscripten_cancel_main_loop(); >>>> and then I call my c code that perform the jpeg stuff. >>>> >>>> Problem is: >>>> the p3stuff function has 2 arguments: int p3stuff(char *imgUrl, >>>> unsigned char *wrappedkey) >>>> When it's called i have two global variables unsigned char *wrappedKey; >>>> and char *imageUrl; which are assigned with the argument like that: >>>> >>>> wrappedKey = wrappedkey; >>>> imageUrl = imgUrl; >>>> >>>> I do that in order to access the image url from the wait_wgets() or the >>>> wrapped key from the onLoaded callback but I think there is some memory >>>> management problems cause if I print the url just before calling >>>> emscripten_async_wget the imageUrl variable content is completely rubbish >>>> but id I don't print anything it works. >>>> >>>> So how can I use the global variables in C in order to not get >>>> overwritten? Maybe using malloc, or memcopy? >>>> >>>> Thanks, >>>> >>>> Pau >>>> >>>> 2015-10-19 10:53 GMT-07:00 Pau Ballart <[email protected]>: >>>> >>>>> Okay I will try the async version and let you know. >>>>> >>>>> Thanks >>>>> >>>>> 2015-10-17 19:37 GMT-07:00 Alon Zakai <[email protected]>: >>>>> >>>>>> The only tricky thing with emscripten_wget is that as mentioned in >>>>>> the docs, >>>>>> >>>>>> >>>>>> http://kripken.github.io/emscripten-site/docs/api_reference/emscripten.h.html#c.emscripten_wget >>>>>> >>>>>> it requires the ASYNCIFY option. It's easier in general to use the >>>>>> async version, emscripten_async_wget, which does not require ASYNCIFY. >>>>>> >>>>>> >>>>>> On Sat, Oct 17, 2015 at 10:47 AM, Pau Ballart <[email protected]> >>>>>> wrote: >>>>>> >>>>>>> I think the php code is correct so I'm just trying to download an >>>>>>> image and process it's data but I think I'm missing something about the >>>>>>> lifecycle or wget function because I get unexpected exit errors. >>>>>>> >>>>>>> So I'd like to know if the emscripten_wget(imgUrl, path); is >>>>>>> correct because I have the weirdest behaviour ever that depending on the >>>>>>> p3stuff function param "wrappedkey" the download succeeds or not. >>>>>>> >>>>>>> 2015-10-15 17:07 GMT-07:00 Alon Zakai <[email protected]>: >>>>>>> >>>>>>>> I see you have >>>>>>>> >>>>>>>> P3Func = Module.cwrap('p3stuff', 'number', ['string', 'string']); >>>>>>>> >>>>>>>> which looks good. You can then call it with something like >>>>>>>> >>>>>>>> result = P3Func('first', 'second'); >>>>>>>> >>>>>>>> which I see you are doing. What part of that are you trying to >>>>>>>> improve? >>>>>>>> >>>>>>>> >>>>>>>> On Thu, Oct 15, 2015 at 12:59 PM, Pau Ballart <[email protected]> >>>>>>>> wrote: >>>>>>>> >>>>>>>>> Okay so the php is just calling a function I declared. Because I >>>>>>>>> need to pass the image url as an argument and a key, I don't know how >>>>>>>>> to do >>>>>>>>> it using the main function so I changed the main function for this >>>>>>>>> one with >>>>>>>>> the two arguments and then called this function from my php code. >>>>>>>>> Is there a better way to call emscripten passing parameters? >>>>>>>>> >>>>>>>>> Thanks. >>>>>>>>> >>>>>>>>> 2015-10-15 12:55 GMT-07:00 Alon Zakai <[email protected]>: >>>>>>>>> >>>>>>>>>> It would be good to focus the question more, it's hard to tell >>>>>>>>>> what the core issue is. Try to reduce the problem to just one >>>>>>>>>> concrete >>>>>>>>>> thing, like just loading a file, and doing it without that custom PHP >>>>>>>>>> script, for example. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Thu, Oct 15, 2015 at 12:27 PM, Pau Ballart <[email protected] >>>>>>>>>> > wrote: >>>>>>>>>> >>>>>>>>>>> Hello developers, >>>>>>>>>>> >>>>>>>>>>> I'm starting a project and I'm new at Javascript and emscripten. >>>>>>>>>>> I'm trying to download some image data from a server and then >>>>>>>>>>> process it >>>>>>>>>>> using some c functions I already have working. I asked this >>>>>>>>>>> question in >>>>>>>>>>> Stackoverflow so I share you the link and maybe one of you can help >>>>>>>>>>> me. >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> http://stackoverflow.com/questions/33087205/emscripten-code-for-image-data-download-using-emscripten-wget-or-emscripten-asyn >>>>>>>>>>> >>>>>>>>>>> Thank you, >>>>>>>>>>> >>>>>>>>>>> Pau B >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>>> Google Groups "emscripten-discuss" group. >>>>>>>>>>> To unsubscribe from this group and stop receiving emails from >>>>>>>>>>> it, send an email to >>>>>>>>>>> [email protected]. >>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> You received this message because you are subscribed to a topic >>>>>>>>>> in the Google Groups "emscripten-discuss" group. >>>>>>>>>> To unsubscribe from this topic, visit >>>>>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>>>>> . >>>>>>>>>> To unsubscribe from this group and all its topics, send an email >>>>>>>>>> to [email protected]. >>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> Pau Ballart >>>>>>>>> >>>>>>>>> -- >>>>>>>>> You received this message because you are subscribed to the Google >>>>>>>>> Groups "emscripten-discuss" group. >>>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>>> send an email to [email protected]. >>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to a topic in >>>>>>>> the Google Groups "emscripten-discuss" group. >>>>>>>> To unsubscribe from this topic, visit >>>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>>> . >>>>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>>>> [email protected]. >>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>> >>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> Pau Ballart >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to the Google >>>>>>> Groups "emscripten-discuss" group. >>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>> send an email to [email protected]. >>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>> >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to a topic in >>>>>> the Google Groups "emscripten-discuss" group. >>>>>> To unsubscribe from this topic, visit >>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>> . >>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>> [email protected]. >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> Pau Ballart >>>>> >>>> >>>> >>>> >>>> -- >>>> Pau Ballart >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "emscripten-discuss" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "emscripten-discuss" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>> . >>> To unsubscribe from this group and all its topics, send an email to >>> [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> Pau Ballart >> >> -- >> You received this message because you are subscribed to the Google Groups >> "emscripten-discuss" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to a topic in the > Google Groups "emscripten-discuss" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- Pau Ballart -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. 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