/* SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0-only */ #include "hexdump.h" #include <ctype.h> static void addrprint(FILE * outfile, uint64_t address, int width); /*-------------------------------------------------------------------------- * hexdump * * Write a hex dump of 'mem' to 'outfile'. * * parameters: * mem: a pointer to the memory to display * bytes: the number of bytes of data to display * addrprint_start: The address to associate with the first byte of * data. For instance, a value of 0 indicates that the * first byte displayed should be labeled as byte 0. * outfile: The place where the hex dump should be written. * For instance, stdout or stderr may be passed here. * format: A structure specifying how the hex dump should be * formatted. *--------------------------------------------------------------------------*/ void hexdump(const void *mem, int bytes, uint64_t addrprint_start, FILE * outfile, const hexdump_format_t * format) { int bytes_left, index, i; const unsigned char *p; /* Quietly return if the caller asks us to do something unreasonable. */ if ((format->bytes_per_line <= 0) || (bytes < 0)) return; p = (const unsigned char *)mem; index = 0; /* Each iteration handles one full line of output. When loop * terminates, the number of remaining bytes to display (if any) * will not be enough to fill an entire line. */ for (bytes_left = bytes; bytes_left >= format->bytes_per_line; bytes_left -= format->bytes_per_line) { /* print start address for current line */ fprintf(outfile, "%s", format->indent); addrprint(outfile, addrprint_start + index, format->addrprint_width); fprintf(outfile, "%s", format->sep1); /* display the bytes in hex */ for (i = 0;;) { fprintf(outfile, "%02x", p[index++]); if (++i >= format->bytes_per_line) break; fprintf(outfile, "%s", format->sep2); } index -= format->bytes_per_line; fprintf(outfile, "%s", format->sep3); /* display the bytes as characters */ for (i = 0; i < format->bytes_per_line; i++, index++) fputc(isprint(p[index])?p[index]:format->nonprintable, outfile); fprintf(outfile, "\n"); } if (bytes_left == 0) return; /* print start address for last line */ fprintf(outfile, "%s", format->indent); addrprint(outfile, addrprint_start + index, format->addrprint_width); fprintf(outfile, "%s", format->sep1); /* display bytes for last line in hex */ for (i = 0; i < bytes_left; i++) { fprintf(outfile, "%02x", p[index++]); fprintf(outfile, "%s", format->sep2); } index -= bytes_left; /* pad the rest of the hex byte area with spaces */ for (;;) { fprintf(outfile, " "); if (++i >= format->bytes_per_line) break; fprintf(outfile, "%s", format->sep2); } fprintf(outfile, "%s", format->sep3); /* display bytes for last line as characters */ for (i = 0; i < bytes_left; i++) fputc(isprint(p[index])?p[index++]:format->nonprintable, outfile); /* pad the rest of the character area with spaces */ for (; i < format->bytes_per_line; i++) fprintf(outfile, " "); fprintf(outfile, "\n"); } /*-------------------------------------------------------------------------- * addrprint * * Display an address as a hexadecimal number. * * parameters: * outfile: the place where the output should be written * address: the address to display * width: The number of bytes wide the address should be displayed as. * Must be a value from 1 to 8. *--------------------------------------------------------------------------*/ static void addrprint(FILE * outfile, uint64_t address, int width) { char s[17]; int i; /* force the user's input to be valid */ if (width < 1) width = 1; else if (width > 8) width = 8; /* convert address to string */ sprintf(s, "%016llx", (unsigned long long)address); /* write it out, with colons separating consecutive 16-bit * chunks of the address */ for (i = 16 - (2 * width);;) { fprintf(outfile, "%c", s[i]); if (++i >= 16) break; if ((i % 4) == 0) fprintf(outfile, ":"); } }