search for: isostat

...ils/isohybrid.c b/utils/isohybrid.c index ff6b930..1c8f0b6 100644 --- a/utils/isohybrid.c +++ b/utils/isohybrid.c @@ -1084,7 +1084,7 @@ main(int argc, char *argv[]) * Primary GPT starts at sector 1, secondary GPT starts at 1 sector * before the end of the image */ - initialise_gpt(buf, 1, (isostat.st_size + padding - 1024) / 512, 1); + initialise_gpt(buf, 1, (isostat.st_size + padding - 512) / 512, 1); if (fseek(fp, 512, SEEK_SET)) err(1, "%s: seek error - 6", argv[0]); @@ -1122,7 +1122,7 @@ main(int argc, char *argv[]) buf += orig_gpt_size - sizeof(struct gpt_header)...

...1..1dcbaa1 100644 --- a/utils/isohybrid.c +++ b/utils/isohybrid.c @@ -36,14 +36,19 @@ #include <unistd.h> #include <sys/stat.h> #include <inttypes.h> +#include <uuid/uuid.h> #include "isohybrid.h" char *prog = NULL; extern int opterr, optind; +struct stat isostat; +unsigned int padding = 0; + +uuid_t disk_uuid, part_uuid, iso_uuid; uint8_t mode = 0; -enum { VERBOSE = 1 }; +enum { VERBOSE = 1 , EFI = 2 , MAC = 4}; /* user options */ uint16_t head = 64; /* 1 <= head <= 256 */ @@ -61,10 +66,150 @@ uint16_t ve[16]; uint32_t catoffset =...

...ll 4 cylinders. Image size is 132.0002489884843 cylinders. So the target size is the next multiple of 4: 136 cylinders. Your algorithm is more complicated than mine, because it tries to do the part of the job which is already implemented in isohybrid: cylsize = head * sector * 512; frac = isostat.st_size % cylsize; padding = (frac > 0) ? cylsize - frac : 0; isostat.st_size is the ISO image size in bytes. cylsize is the current granularity of 1 cylinder. My proposal has 1, 2, or 4 cylinders instead. cylsize = head * sector * 512; align_cylsize = cylsize * align_factor; f...

Hi, following will be 6 patch proposals for isohybrid.c 1: Encode GPT partition names as UTF-16LE 2: Correct blocking factor in APM partition block counts 3: Correct end block address of first GPT partition 4: Write GPT backup to the very end of the image 5: Change all fseek(3) to fseeko(3) 6: Introduce option --mbr and make isohybrid.c compilable standalone If the form needs adjustments,

> > Same result as yours. > > > Have a nice day :) > > Thomas > I was under the impression (apparently the wrong one) that your pseudo-code was adding 4 cylinders to the first example, from 132 to 136, which would be non-optimal. Since I am not a developer, I believe you when you say that such jump won't happen :). Perhaps the code will be more clear to me

Hello Recently while playing with bigger iso images (>2G) looks like isohybrid from syslinux-4.02 fails. Sometimes tunning heads/sectors (-h/-s) works, because no padding is needed depending of size of the image. Some debug info provided, if more info is needed please just ask. # isohybrid -v pandereta-2010.09.13-i686.iso catalogue offset: 326 ve[0]: 1, cs: 1 ve[1]: 0, cs: 1 ve[2]: 25927,

...display_mbr(buf, i); - if (fseek(fp, 0, SEEK_SET)) + if (fseeko(fp, (off_t) 0, SEEK_SET)) err(1, "%s: seek error - 5", argv[0]); if (fwrite(buf, sizeof(char), i, fp) != (size_t)i) @@ -1086,7 +1086,7 @@ main(int argc, char *argv[]) */ initialise_gpt(buf, 1, (isostat.st_size + padding - 512) / 512, 1); - if (fseek(fp, 512, SEEK_SET)) + if (fseeko(fp, (off_t) 512, SEEK_SET)) err(1, "%s: seek error - 6", argv[0]); if (fwrite(buf, sizeof(char), gpt_size, fp) != (size_t)gpt_size) @@ -1103,7 +1103,7 @@ main(int argc, char *argv[]) initialis...

...ize = 0, frac = 0, align_factor, align_cylsize; size_t orig_gpt_size, free_space, gpt_size; struct iso_primary_descriptor descriptor; @@ -1058,9 +1058,20 @@ main(int argc, char *argv[]) isosize = lendian_int(descriptor.size) * lendian_short(descriptor.block_size); free_space = isostat.st_size - isosize; + /* Making sure that the resulting image size is divisible by 2048. + (Can waste nearly 32 MB. Should be done on user request only.) + */ + if ((head * sector) % 4 == 0) + align_factor = 1; + else if ((head * sector) % 2 == 0) + align_factor = 2...

> Hi, > > > Hopefully I am explaining it better this time. > > Our ideas of implementation are supposed to yield the > same result. > Hmm, I am not sure. Or perhaps I am misunderstanding your code. Let me try with an example (or two). For this example, let's assume: -h 255 -s 63 ISO size: 1'085'736'960 bytes ( > 1GiB) This size happens to be a

...utils/isohybrid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/utils/isohybrid.c b/utils/isohybrid.c index 410bb60..23fc6c0 100644 --- a/utils/isohybrid.c +++ b/utils/isohybrid.c @@ -1126,7 +1126,7 @@ main(int argc, char *argv[]) * end of the image */ - if (fseek(fp, (isostat.st_size + padding) - orig_gpt_size - 512, + if (fseeko(fp, (isostat.st_size + padding) - orig_gpt_size - 512, SEEK_SET)) err(1, "%s: seek error - 8", argv[0]); -- 1.9.1

Hi, > Hopefully I am explaining it better this time. Our ideas of implementation are supposed to yield the same result. As said, i am willing to implement my proposal in a copy of isohybrid.c, if somebody wants to test it. Advantages and disadvantages should be obvious. Interested users please send util/isohybrid.c from your local SYSLINUX source code installation to me. Just to be sure

...e, gpt_size, real_offset; struct iso_primary_descriptor descriptor; prog = strcpy(alloca(strlen(argv[0]) + 1), argv[0]); @@ -1125,9 +1126,16 @@ main(int argc, char *argv[]) * Seek far enough back that the gpt header is 512 bytes before the * end of the image */ + real_offset = (isostat.st_size + padding) - orig_gpt_size - 512; - if (fseek(fp, (isostat.st_size + padding) - orig_gpt_size - 512, - SEEK_SET)) + fseek(fp, 0, SEEK_SET); + while (real_offset > LONG_MAX) { + if (fseek(fp, LONG_MAX, SEEK_CUR)) + err(1, "%s: seek error - 8", argv[0]); + real_offset -=...

...or = 1 else if (Heads * Sectors_per_track) is divisible by 2 # Pad up to next full double cylinder align_factor = 2 else # Pad up to next full quatruple cylinder (nearly 32 MB) align_factor = 4 In isohybrid.c the resulting align_factor would be used like this: - frac = isostat.st_size % cylsize; - padding = (frac > 0) ? cylsize - frac : 0; + align_cylsize = cylsize * align_factor; + frac = isostat.st_size % align_cylsize; + padding = (frac > 0) ? align_cylsize - frac : 0; Similarly in isohybrid.in. There is no risk that the larger padding would exceed...

> Hi, > > Ady wrote: > > I am not so sure that using a different pair of '-h' and '-s' values > > would be better than using 255/63. > > But 255 * 63 is not divisible by 4 and thus can cause > trouble with virtual DVD-ROM. And my suggestion to modify the _amount_ of Cylinders was intended to overcome the "by 4" (or rather, "by

...offset * 2048, SEEK_SET)) The call has to become something like if (fseeko(fp, ((off_t) catoffset) * 2048, SEEK_SET)) Adresses which are surely smaller than 31 bit could be left unchanged. E.g.: if (fseek(fp, 17 * 2048, SEEK_SET)) Kai Kang's change is already (off_t), because of isostat.st_size as of man 2 stat. Have a nice day :) Thomas

Hi, i am currently exploring the boot data of Matthew Garret's Fedora LiveCD. For that i read utils/isohybrid.c from git resp. 4.05. (I assume Matthew used options --efi --mac --type 0 .) Some stumblestones showed up: ----------------------------------------------------------------------- In initialise_gpt() i see unhealthy usage of string constants. Like: memcpy(part->name,

Hi, Ady wrote: > I am not so sure that using a different pair of '-h' and '-s' values > would be better than using 255/63. But 255 * 63 is not divisible by 4 and thus can cause trouble with virtual DVD-ROM. > Most BIOS and most partition editors would assume this geometry. I cannot tell for BIOSes, but partition editors have options to set heads-per-cyl and

> Hi, > > at [Tails] we're in the process of shipping hybrid ISO images by > default again. We're using `isohybrid -h 255 -s 63' to do that (thanks > to the advice we got on this mailing-list a few months ago!). > > And then, we've discovered that sometimes, isohybrid produces ISO > images whose size is not a multiple of 2048 bytes. > > Who cares?

...2048 bytes. Seems to be intentional. http://git.kernel.org/cgit/boot/syslinux/syslinux.git/tree/utils/isohybrid.in # Target image size: round up to a multiple of $h*$s*512 http://git.kernel.org/cgit/boot/syslinux/syslinux.git/tree/utils/isohybrid.c cylsize = head * sector * 512; frac = isostat.st_size % cylsize; padding = (frac > 0) ? cylsize - frac : 0; With -h 255 -s 63, both pad to an integer number of cylinders with an impair multiple of 512 bytes. So if the number of cylinders is not divisible by 4, then the number of bytes is not divisible by 2048. An ISO image may have a...

Hi, at [Tails] we're in the process of shipping hybrid ISO images by default again. We're using `isohybrid -h 255 -s 63' to do that (thanks to the advice we got on this mailing-list a few months ago!). And then, we've discovered that sometimes, isohybrid produces ISO images whose size is not a multiple of 2048 bytes. Who cares? ... may you ask. Well, apparently, VirtualBox does: