/* ----------------------------------------------------------------------- * * * Copyright 1996-2014 The NASM Authors - All Rights Reserved * See the file AUTHORS included with the NASM distribution for * the specific copyright holders. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following * conditions are met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials provided * with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * ----------------------------------------------------------------------- */ /* * ldrdf.c - RDOFF Object File linker/loader main program. */ /* * TODO: * - enhance search of required export symbols in libraries (now depends * on modules order in library) * - keep a cache of symbol names in each library module so * we don't have to constantly recheck the file * - general performance improvements * * BUGS & LIMITATIONS: this program doesn't support multiple code, data * or bss segments, therefore for 16 bit programs whose code, data or BSS * segment exceeds 64K in size, it will not work. This program probably * won't work if compiled by a 16 bit compiler. Try DJGPP if you're running * under DOS. '#define STINGY_MEMORY' may help a little. */ #include "compiler.h" #include #include #include "rdfutils.h" #include "symtab.h" #include "collectn.h" #include "rdlib.h" #include "segtab.h" #include "nasmlib.h" #define LDRDF_VERSION "1.08" /* #define STINGY_MEMORY */ /* ======================================================================= * Types & macros that are private to this program */ struct segment_infonode { int dest_seg; /* output segment to be placed into, -1 to skip linking this segment */ int32_t reloc; /* segment's relocation factor */ }; struct modulenode { rdffile f; /* the RDOFF file structure */ struct segment_infonode seginfo[RDF_MAXSEGS]; /* what are we doing with each segment? */ void *header; char *name; struct modulenode *next; int32_t bss_reloc; }; #include "ldsegs.h" /* ========================================================================== * Function prototypes of private utility functions */ void processmodule(const char *filename, struct modulenode *mod); int allocnewseg(uint16_t type, uint16_t reserved); int findsegment(uint16_t type, uint16_t reserved); void symtab_add(const char *symbol, int segment, int32_t offset); int symtab_get(const char *symbol, int *segment, int32_t *offset); /* ========================================================================= * Global data structures. */ /* a linked list of modules that will be included in the output */ struct modulenode *modules = NULL; struct modulenode *lastmodule = NULL; /* a linked list of libraries to be searched for unresolved imported symbols */ struct librarynode *libraries = NULL; struct librarynode *lastlib = NULL; /* the symbol table */ void *symtab = NULL; /* objects search path */ char *objpath = NULL; /* libraries search path */ char *libpath = NULL; /* file to embed as a generic record */ char *generic_rec_file = NULL; /* module name to be added at the beginning of output file */ char *modname_specified = NULL; /* the header of the output file, built up stage by stage */ rdf_headerbuf *newheader = NULL; /* The current state of segment allocation, including information about * which output segment numbers have been allocated, and their types and * amount of data which has already been allocated inside them. */ struct SegmentHeaderRec outputseg[RDF_MAXSEGS]; int nsegs = 0; int32_t bss_length; /* global options which affect how the program behaves */ struct ldrdfoptions { int verbose; int align; int dynalink; int strip; int respfile; int stderr_redir; int objpath; int libpath; } options; int errorcount = 0; /* determines main program exit status */ /* ========================================================================= * Utility functions */ /* * initsegments() * * sets up segments 0, 1, and 2, the initial code data and bss segments */ static void initsegments(void) { nsegs = 3; outputseg[0].type = 1; outputseg[0].number = 0; outputseg[0].reserved = 0; outputseg[0].length = 0; outputseg[1].type = 2; outputseg[1].number = 1; outputseg[1].reserved = 0; outputseg[1].length = 0; outputseg[2].type = 0xFFFF; /* reserved segment type */ outputseg[2].number = 2; outputseg[2].reserved = 0; outputseg[2].length = 0; bss_length = 0; } /* * loadmodule() * * Determine the characteristics of a module, and decide what to do with * each segment it contains (including determining destination segments and * relocation factors for segments that are kept). */ static void loadmodule(const char *filename) { if (options.verbose) printf("loading `%s'\n", filename); /* allocate a new module entry on the end of the modules list */ if (!modules) { modules = nasm_malloc(sizeof(*modules)); lastmodule = modules; } else { lastmodule->next = nasm_malloc(sizeof(*modules)); lastmodule = lastmodule->next; } if (!lastmodule) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } /* open the file using 'rdfopen', which returns nonzero on error */ if (rdfopen(&lastmodule->f, filename) != 0) { rdfperror("ldrdf", filename); exit(1); } /* * store information about the module, and determine what segments * it contains, and what we should do with them (determine relocation * factor if we decide to keep them) */ lastmodule->header = NULL; lastmodule->name = nasm_strdup(filename); lastmodule->next = NULL; processmodule(filename, lastmodule); } /* * processmodule() * * step through each segment, determine what exactly we're doing with * it, and if we intend to keep it, determine (a) which segment to * put it in and (b) whereabouts in that segment it will end up. * (b) is fairly easy, because we're now keeping track of how big each * segment in our output file is... */ void processmodule(const char *filename, struct modulenode *mod) { struct segconfig sconf; int seg, outseg; void *header; rdfheaderrec *hr; int32_t bssamount = 0; int bss_was_referenced = 0; memset(&sconf, 0, sizeof sconf); for (seg = 0; seg < mod->f.nsegs; seg++) { /* * get the segment configuration for this type from the segment * table. getsegconfig() is a macro, defined in ldsegs.h. */ getsegconfig(sconf, mod->f.seg[seg].type); if (options.verbose > 1) { printf("%s %04x [%04x:%10s] ", filename, mod->f.seg[seg].number, mod->f.seg[seg].type, sconf.typedesc); } /* * sconf->dowhat tells us what to do with a segment of this type. */ switch (sconf.dowhat) { case SEG_IGNORE: /* * Set destination segment to -1, to indicate that this segment * should be ignored for the purpose of output, ie it is left * out of the linked executable. */ mod->seginfo[seg].dest_seg = -1; if (options.verbose > 1) printf("IGNORED\n"); break; case SEG_NEWSEG: /* * The configuration tells us to create a new segment for * each occurrence of this segment type. */ outseg = allocnewseg(sconf.mergetype, mod->f.seg[seg].reserved); mod->seginfo[seg].dest_seg = outseg; mod->seginfo[seg].reloc = 0; outputseg[outseg].length = mod->f.seg[seg].length; if (options.verbose > 1) printf("=> %04x:%08"PRIx32" (+%04"PRIx32")\n", outseg, mod->seginfo[seg].reloc, mod->f.seg[seg].length); break; case SEG_MERGE: /* * The configuration tells us to merge the segment with * a previously existing segment of type 'sconf.mergetype', * if one exists. Otherwise a new segment is created. * This is handled transparently by 'findsegment()'. */ outseg = findsegment(sconf.mergetype, mod->f.seg[seg].reserved); mod->seginfo[seg].dest_seg = outseg; /* * We need to add alignment to these segments. */ if (outputseg[outseg].length % options.align != 0) outputseg[outseg].length += options.align - (outputseg[outseg].length % options.align); mod->seginfo[seg].reloc = outputseg[outseg].length; outputseg[outseg].length += mod->f.seg[seg].length; if (options.verbose > 1) printf("=> %04x:%08"PRIx32" (+%04"PRIx32")\n", outseg, mod->seginfo[seg].reloc, mod->f.seg[seg].length); } } /* * extract symbols from the header, and dump them into the * symbol table */ header = nasm_malloc(mod->f.header_len); if (!header) { fprintf(stderr, "ldrdf: not enough memory\n"); exit(1); } if (rdfloadseg(&mod->f, RDOFF_HEADER, header)) { rdfperror("ldrdf", filename); exit(1); } while ((hr = rdfgetheaderrec(&mod->f))) { switch (hr->type) { case RDFREC_IMPORT: /* imported symbol */ case RDFREC_FARIMPORT: /* Define with seg = -1 */ symtab_add(hr->i.label, -1, 0); break; case RDFREC_GLOBAL:{ /* exported symbol */ int destseg; int32_t destreloc; if (hr->e.segment == 2) { bss_was_referenced = 1; destreloc = bss_length; if (destreloc % options.align != 0) destreloc += options.align - (destreloc % options.align); destseg = 2; } else { if ((destseg = mod->seginfo[(int)hr->e.segment].dest_seg) == -1) continue; destreloc = mod->seginfo[(int)hr->e.segment].reloc; } symtab_add(hr->e.label, destseg, destreloc + hr->e.offset); break; } case RDFREC_BSS: /* BSS reservation */ /* * first, amalgamate all BSS reservations in this module * into one, because we allow this in the output format. */ bssamount += hr->b.amount; break; case RDFREC_COMMON:{ /* Common variable */ symtabEnt *ste = symtabFind(symtab, hr->c.label); /* Is the symbol already in the table? */ if (ste) break; /* Align the variable */ if (bss_length % hr->c.align != 0) bss_length += hr->c.align - (bss_length % hr->c.align); if (options.verbose > 1) { printf("%s %04x common '%s' => 0002:%08"PRIx32" (+%04"PRIx32")\n", filename, hr->c.segment, hr->c.label, bss_length, hr->c.size); } symtab_add(hr->c.label, 2, bss_length); mod->bss_reloc = bss_length; bss_length += hr->c.size; break; } } } if (bssamount != 0 || bss_was_referenced) { /* * handle the BSS segment - first pad the existing bss length * to the correct alignment, then store the length in bss_reloc * for this module. Then add this module's BSS length onto * bss_length. */ if (bss_length % options.align != 0) bss_length += options.align - (bss_length % options.align); mod->bss_reloc = bss_length; if (options.verbose > 1) { printf("%s 0002 [ BSS] => 0002:%08"PRIx32" (+%04"PRIx32")\n", filename, bss_length, bssamount); } bss_length += bssamount; } #ifdef STINGY_MEMORY /* * we free the header buffer here, to save memory later. * this isn't efficient, but probably halves the memory usage * of this program... */ mod->f.header_loc = NULL; nasm_free(header); #endif } /* * Return 1 if a given module is in the list, 0 otherwise. */ static int lookformodule(const char *name) { struct modulenode *curr = modules; while (curr) { if (!strcmp(name, curr->name)) return 1; curr = curr->next; } return 0; } /* * allocnewseg() * findsegment() * * These functions manipulate the array of output segments, and are used * by processmodule(). allocnewseg() allocates a segment in the array, * initialising it to be empty. findsegment() first scans the array for * a segment of the type requested, and if one isn't found allocates a * new one. */ int allocnewseg(uint16_t type, uint16_t reserved) { outputseg[nsegs].type = type; outputseg[nsegs].number = nsegs; outputseg[nsegs].reserved = reserved; outputseg[nsegs].length = 0; outputseg[nsegs].offset = 0; outputseg[nsegs].data = NULL; return nsegs++; } int findsegment(uint16_t type, uint16_t reserved) { int i; for (i = 0; i < nsegs; i++) if (outputseg[i].type == type) return i; return allocnewseg(type, reserved); } /* * symtab_add() * * inserts a symbol into the global symbol table, which associates symbol * names either with addresses, or a marker that the symbol hasn't been * resolved yet, or possibly that the symbol has been defined as * contained in a dynamic [load time/run time] linked library. * * segment = -1 => not yet defined * segment = -2 => defined as dll symbol * * If the symbol is already defined, and the new segment >= 0, then * if the original segment was < 0 the symbol is redefined, otherwise * a duplicate symbol warning is issued. If new segment == -1, this * routine won't change a previously existing symbol. It will change * to segment = -2 only if the segment was previously < 0. */ void symtab_add(const char *symbol, int segment, int32_t offset) { symtabEnt *ste; ste = symtabFind(symtab, symbol); if (ste) { if (ste->segment >= 0) { /* * symbol previously defined */ if (segment < 0) return; fprintf(error_file, "warning: `%s' redefined\n", symbol); return; } /* * somebody wanted the symbol, and put an undefined symbol * marker into the table */ if (segment == -1) return; /* * we have more information now - update the symbol's entry */ ste->segment = segment; ste->offset = offset; ste->flags = 0; return; } /* * this is the first declaration of this symbol */ ste = nasm_malloc(sizeof(symtabEnt)); if (!ste) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } ste->name = nasm_strdup(symbol); ste->segment = segment; ste->offset = offset; ste->flags = 0; symtabInsert(symtab, ste); } /* * symtab_get() * * Retrieves the values associated with a symbol. Undefined symbols * are assumed to have -1:0 associated. Returns 1 if the symbol was * successfully located. */ int symtab_get(const char *symbol, int *segment, int32_t *offset) { symtabEnt *ste = symtabFind(symtab, symbol); if (!ste) { *segment = -1; *offset = 0; return 0; } else { *segment = ste->segment; *offset = ste->offset; return 1; } } /* * add_library() * * checks that a library can be opened and is in the correct format, * then adds it to the linked list of libraries. */ static void add_library(const char *name) { if (rdl_verify(name)) { rdl_perror("ldrdf", name); errorcount++; return; } if (!libraries) { lastlib = libraries = nasm_malloc(sizeof(*libraries)); if (!libraries) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } } else { lastlib->next = nasm_malloc(sizeof(*libraries)); if (!lastlib->next) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } lastlib = lastlib->next; } lastlib->next = NULL; if (rdl_open(lastlib, name)) { rdl_perror("ldrdf", name); errorcount++; return; } } /* * search_libraries() * * scans through the list of libraries, attempting to match symbols * defined in library modules against symbols that are referenced but * not defined (segment = -1 in the symbol table) * * returns 1 if any extra library modules are included, indicating that * another pass through the library list should be made (possibly). */ static int search_libraries(void) { struct librarynode *cur; rdffile f; int i; void *header; int segment; int32_t offset; int doneanything = 0, pass = 1, keepfile; rdfheaderrec *hr; cur = libraries; while (cur) { if (options.verbose > 2) printf("scanning library `%s', pass %d...\n", cur->name, pass); for (i = 0; rdl_openmodule(cur, i, &f) == 0; i++) { if (pass == 2 && lookformodule(f.name)) continue; if (options.verbose > 3) printf(" looking in module `%s'\n", f.name); header = nasm_malloc(f.header_len); if (!header) { fprintf(stderr, "ldrdf: not enough memory\n"); exit(1); } if (rdfloadseg(&f, RDOFF_HEADER, header)) { rdfperror("ldrdf", f.name); errorcount++; return 0; } keepfile = 0; while ((hr = rdfgetheaderrec(&f))) { /* We're only interested in exports, so skip others */ if (hr->type != RDFREC_GLOBAL) continue; /* * If the symbol is marked as SYM_GLOBAL, somebody will be * definitely interested in it.. */ if ((hr->e.flags & SYM_GLOBAL) == 0) { /* * otherwise the symbol is just public. Find it in * the symbol table. If the symbol isn't defined, we * aren't interested, so go on to the next. * If it is defined as anything but -1, we're also not * interested. But if it is defined as -1, insert this * module into the list of modules to use, and go * immediately on to the next module... */ if (!symtab_get(hr->e.label, &segment, &offset) || segment != -1) continue; } doneanything = 1; keepfile = 1; /* * as there are undefined symbols, we can assume that * there are modules on the module list by the time * we get here. */ lastmodule->next = nasm_malloc(sizeof(*lastmodule->next)); if (!lastmodule->next) { fprintf(stderr, "ldrdf: not enough memory\n"); exit(1); } lastmodule = lastmodule->next; memcpy(&lastmodule->f, &f, sizeof(f)); lastmodule->name = nasm_strdup(f.name); lastmodule->next = NULL; processmodule(f.name, lastmodule); break; } if (!keepfile) { nasm_free(f.name); f.name = NULL; f.fp = NULL; } } if (rdl_error != 0 && rdl_error != RDL_ENOTFOUND) rdl_perror("ldrdf", cur->name); cur = cur->next; if (cur == NULL && pass == 1) { cur = libraries; pass++; } } return doneanything; } /* * write_output() * * this takes the linked list of modules, and walks through it, merging * all the modules into a single output module, and then writes this to a * file. */ static void write_output(const char *filename) { FILE *f; rdf_headerbuf *rdfheader; struct modulenode *cur; int i, n, availableseg, seg, localseg, isrelative; void *header; rdfheaderrec *hr, newrec; symtabEnt *se; segtab segs; int32_t offset; uint8_t *data; if ((f = fopen(filename, "wb")) == NULL) { fprintf(stderr, "ldrdf: couldn't open %s for output\n", filename); exit(1); } if ((rdfheader = rdfnewheader()) == NULL) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } /* * If '-g' option was given, first record in output file will be a * `generic' record, filled with a given file content. * This can be useful, for example, when constructing multiboot * compliant kernels. */ if (generic_rec_file) { FILE *ff; if (options.verbose) printf("\nadding generic record from binary file %s\n", generic_rec_file); hr = (rdfheaderrec *) nasm_malloc(sizeof(struct GenericRec)); if ((ff = fopen(generic_rec_file, "r")) == NULL) { fprintf(stderr, "ldrdf: couldn't open %s for input\n", generic_rec_file); exit(1); } n = fread(hr->g.data, 1, sizeof(hr->g.data), ff); fseek(ff, 0, SEEK_END); if (ftell(ff) > (long)sizeof(hr->g.data)) { fprintf(error_file, "warning: maximum generic record size is %u, " "rest of file ignored\n", (unsigned int)sizeof(hr->g.data)); } fclose(ff); hr->g.type = RDFREC_GENERIC; hr->g.reclen = n; rdfaddheader(rdfheader, hr); nasm_free(hr); } /* * Add module name record if `-mn' option was given */ if (modname_specified) { n = strlen(modname_specified); if ((n < 1) || (n >= MODLIB_NAME_MAX)) { fprintf(stderr, "ldrdf: invalid length of module name `%s'\n", modname_specified); exit(1); } if (options.verbose) printf("\nadding module name record %s\n", modname_specified); hr = (rdfheaderrec *) nasm_malloc(sizeof(struct ModRec)); hr->m.type = RDFREC_MODNAME; hr->m.reclen = n + 1; strcpy(hr->m.modname, modname_specified); rdfaddheader(rdfheader, hr); nasm_free(hr); } if (options.verbose) printf("\nbuilding output module (%d segments)\n", nsegs); /* * Allocate the memory for the segments. We may be better off * building the output module one segment at a time when running * under 16 bit DOS, but that would be a slower way of doing this. * And you could always use DJGPP... */ for (i = 0; i < nsegs; i++) { outputseg[i].data = NULL; if (!outputseg[i].length) continue; outputseg[i].data = nasm_malloc(outputseg[i].length); if (!outputseg[i].data) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } } /* * initialise availableseg, used to allocate segment numbers for * imported and exported labels... */ availableseg = nsegs; /* * Step through the modules, performing required actions on each one */ for (cur = modules; cur; cur = cur->next) { /* * Read the actual segment contents into the correct places in * the newly allocated segments */ for (i = 0; i < cur->f.nsegs; i++) { int dest = cur->seginfo[i].dest_seg; if (dest == -1) continue; if (rdfloadseg(&cur->f, i, outputseg[dest].data + cur->seginfo[i].reloc)) { rdfperror("ldrdf", cur->name); exit(1); } } /* * Perform fixups, and add new header records where required */ header = nasm_malloc(cur->f.header_len); if (!header) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } if (cur->f.header_loc) rdfheaderrewind(&cur->f); else if (rdfloadseg(&cur->f, RDOFF_HEADER, header)) { rdfperror("ldrdf", cur->name); exit(1); } /* * we need to create a local segment number -> location * table for the segments in this module. */ init_seglocations(&segs); for (i = 0; i < cur->f.nsegs; i++) { add_seglocation(&segs, cur->f.seg[i].number, cur->seginfo[i].dest_seg, cur->seginfo[i].reloc); } /* * and the BSS segment (doh!) */ add_seglocation(&segs, 2, 2, cur->bss_reloc); while ((hr = rdfgetheaderrec(&cur->f))) { switch (hr->type) { case RDFREC_RELOC: /* relocation record - need to do a fixup */ /* * First correct the offset stored in the segment from * the start of the segment (which may well have changed). * * To do this we add to the number stored the relocation * factor associated with the segment that contains the * target segment. * * The relocation could be a relative relocation, in which * case we have to first subtract the amount we've relocated * the containing segment by. */ if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset)) { fprintf(stderr, "%s: reloc to undefined segment %04x\n", cur->name, (int)hr->r.refseg); errorcount++; break; } isrelative = (hr->r.segment & RDOFF_RELATIVEMASK) == RDOFF_RELATIVEMASK; hr->r.segment &= (RDOFF_RELATIVEMASK - 1); if (hr->r.segment == 2 || (localseg = rdffindsegment(&cur->f, hr->r.segment)) == -1) { fprintf(stderr, "%s: reloc from %s segment (%d)\n", cur->name, hr->r.segment == 2 ? "BSS" : "unknown", hr->r.segment); errorcount++; break; } if (hr->r.length != 1 && hr->r.length != 2 && hr->r.length != 4) { fprintf(stderr, "%s: nonstandard length reloc " "(%d bytes)\n", cur->name, hr->r.length); errorcount++; break; } /* * okay, now the relocation is in the segment pointed to by * cur->seginfo[localseg], and we know everything else is * okay to go ahead and do the relocation */ data = outputseg[cur->seginfo[localseg].dest_seg].data; data += cur->seginfo[localseg].reloc + hr->r.offset; /* * data now points to the reference that needs * relocation. Calculate the relocation factor. * Factor is: * offset of referred object in segment [in offset] * (- relocation of localseg, if ref is relative) * For simplicity, the result is stored in 'offset'. * Then add 'offset' onto the value at data. */ if (isrelative) offset -= cur->seginfo[localseg].reloc; switch (hr->r.length) { case 1: offset += *data; if (offset < -127 || offset > 128) fprintf(error_file, "warning: relocation out of range " "at %s(%02x:%08"PRIx32")\n", cur->name, (int)hr->r.segment, hr->r.offset); *data = (char)offset; break; case 2: offset += *(int16_t *)data; if (offset < -32767 || offset > 32768) fprintf(error_file, "warning: relocation out of range " "at %s(%02x:%08"PRIx32")\n", cur->name, (int)hr->r.segment, hr->r.offset); *(int16_t *)data = (int16_t)offset; break; case 4: *(int32_t *)data += offset; /* we can't easily detect overflow on this one */ break; } /* * If the relocation was relative between two symbols in * the same segment, then we're done. * * Otherwise, we need to output a new relocation record * with the references updated segment and offset... */ if (!isrelative || cur->seginfo[localseg].dest_seg != seg) { hr->r.segment = cur->seginfo[localseg].dest_seg; hr->r.offset += cur->seginfo[localseg].reloc; hr->r.refseg = seg; if (isrelative) hr->r.segment += RDOFF_RELATIVEMASK; rdfaddheader(rdfheader, hr); } break; case RDFREC_IMPORT: /* import symbol */ case RDFREC_FARIMPORT: /* * scan the global symbol table for the symbol * and associate its location with the segment number * for this module */ se = symtabFind(symtab, hr->i.label); if (!se || se->segment == -1) { if (!options.dynalink && !(hr->i.flags & SYM_IMPORT)) { fprintf(error_file, "error: unresolved reference to `%s'" " in module `%s'\n", hr->i.label, cur->name); errorcount++; } /* * we need to allocate a segment number for this * symbol, and store it in the symbol table for * future reference */ if (!se) { se = nasm_malloc(sizeof(*se)); if (!se) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } se->name = nasm_strdup(hr->i.label); se->flags = 0; se->segment = availableseg++; se->offset = 0; symtabInsert(symtab, se); } else { se->segment = availableseg++; se->offset = 0; } /* * output a header record that imports it to the * recently allocated segment number... */ newrec = *hr; newrec.i.segment = se->segment; rdfaddheader(rdfheader, &newrec); } add_seglocation(&segs, hr->i.segment, se->segment, se->offset); break; case RDFREC_GLOBAL: /* export symbol */ /* * need to insert an export for this symbol into the new * header, unless we're stripping symbols. Even if we're * stripping, put the symbol if it's marked as SYM_GLOBAL. */ if (options.strip && !(hr->e.flags & SYM_GLOBAL)) break; if (hr->e.segment == 2) { seg = 2; offset = cur->bss_reloc; } else { localseg = rdffindsegment(&cur->f, hr->e.segment); if (localseg == -1) { fprintf(stderr, "%s: exported symbol `%s' from " "unrecognised segment\n", cur->name, hr->e.label); errorcount++; break; } offset = cur->seginfo[localseg].reloc; seg = cur->seginfo[localseg].dest_seg; } hr->e.segment = seg; hr->e.offset += offset; rdfaddheader(rdfheader, hr); break; case RDFREC_MODNAME: /* module name */ /* * Insert module name record if export symbols * are not stripped. * If module name begins with '$' - insert it anyway. */ if (options.strip && hr->m.modname[0] != '$') break; rdfaddheader(rdfheader, hr); break; case RDFREC_DLL: /* DLL name */ /* * Insert DLL name if it begins with '$' */ if (hr->d.libname[0] != '$') break; rdfaddheader(rdfheader, hr); break; case RDFREC_SEGRELOC: /* segment fixup */ /* * modify the segment numbers if necessary, and * pass straight through to the output module header * * *** FIXME *** */ if (hr->r.segment == 2) { fprintf(stderr, "%s: segment fixup in BSS section\n", cur->name); errorcount++; break; } localseg = rdffindsegment(&cur->f, hr->r.segment); if (localseg == -1) { fprintf(stderr, "%s: segment fixup in unrecognised" " segment (%d)\n", cur->name, hr->r.segment); errorcount++; break; } hr->r.segment = cur->seginfo[localseg].dest_seg; hr->r.offset += cur->seginfo[localseg].reloc; if (!get_seglocation(&segs, hr->r.refseg, &seg, &offset)) { fprintf(stderr, "%s: segment fixup to undefined " "segment %04x\n", cur->name, (int)hr->r.refseg); errorcount++; break; } hr->r.refseg = seg; rdfaddheader(rdfheader, hr); break; case RDFREC_COMMON: /* Common variable */ /* Is this symbol already in the table? */ se = symtabFind(symtab, hr->c.label); if (!se) { printf("%s is not in symtab yet\n", hr->c.label); break; } /* Add segment location */ add_seglocation(&segs, hr->c.segment, se->segment, se->offset); break; } } nasm_free(header); done_seglocations(&segs); } /* * combined BSS reservation for the entire results */ newrec.type = RDFREC_BSS; newrec.b.reclen = 4; newrec.b.amount = bss_length; rdfaddheader(rdfheader, &newrec); /* * Write the header */ for (i = 0; i < nsegs; i++) { if (i == 2) continue; rdfaddsegment(rdfheader, outputseg[i].length); } rdfwriteheader(f, rdfheader); rdfdoneheader(rdfheader); /* * Step through the segments, one at a time, writing out into * the output file */ for (i = 0; i < nsegs; i++) { if (i == 2) continue; fwriteint16_t(outputseg[i].type, f); fwriteint16_t(outputseg[i].number, f); fwriteint16_t(outputseg[i].reserved, f); fwriteint32_t(outputseg[i].length, f); nasm_write(outputseg[i].data, outputseg[i].length, f); } fwritezero(10, f); } /* ========================================================================= * Main program */ static void usage(void) { printf("usage:\n" " ldrdf [options] object modules ... [-llibrary ...]\n" " ldrdf -r\n" "options:\n" " -v[=n] increase verbosity by 1, or set it to n\n" " -a nn set segment alignment value (default 16)\n" " -s strip public symbols\n" " -dy Unix-style dynamic linking\n" " -o name write output in file 'name'\n" " -j path specify objects search path\n" " -L path specify libraries search path\n" " -g file embed 'file' as a first header record with type 'generic'\n" " -mn name add module name record at the beginning of output file\n"); exit(0); } int main(int argc, char **argv) { char *outname = "aout.rdf"; int moduleloaded = 0; char *respstrings[128] = { 0, }; rdoff_init(); options.verbose = 0; options.align = 16; options.dynalink = 0; options.strip = 0; error_file = stderr; argc--, argv++; if (argc == 0) usage(); while (argc && *argv && **argv == '-' && argv[0][1] != 'l') { switch (argv[0][1]) { case 'r': printf("ldrdf (linker for RDF files) version " LDRDF_VERSION "\n"); printf("RDOFF2 revision %s\n", RDOFF2_REVISION); exit(0); case 'v': if (argv[0][2] == '=') { options.verbose = argv[0][3] - '0'; if (options.verbose < 0 || options.verbose > 9) { fprintf(stderr, "ldrdf: verbosity level must be a number" " between 0 and 9\n"); exit(1); } } else options.verbose++; break; case 'a': options.align = atoi(argv[1]); if (options.align <= 0) { fprintf(stderr, "ldrdf: -a expects a positive number argument\n"); exit(1); } argv++, argc--; break; case 's': options.strip = 1; break; case 'd': if (argv[0][2] == 'y') options.dynalink = 1; break; case 'm': if (argv[0][2] == 'n') { modname_specified = argv[1]; argv++, argc--; if (!argc) { fprintf(stderr, "ldrdf: -mn expects a module name\n"); exit(1); } } break; case 'o': outname = argv[1]; argv++, argc--; break; case 'j': if (!objpath) { options.objpath = 1; objpath = argv[1]; argv++, argc--; break; } else { fprintf(stderr, "ldrdf: more than one objects search path specified\n"); exit(1); } case 'L': if (!libpath) { options.libpath = 1; libpath = argv[1]; argv++, argc--; break; } else { fprintf(stderr, "ldrdf: more than one libraries search path specified\n"); exit(1); } case '@':{ int i = 0; char buf[256]; FILE *f; options.respfile = 1; if (argv[1] != NULL) f = fopen(argv[1], "r"); else { fprintf(stderr, "ldrdf: no response file name specified\n"); exit(1); } if (f == NULL) { fprintf(stderr, "ldrdf: unable to open response file\n"); exit(1); } argv++, argc--; while (fgets(buf, sizeof(buf), f) != NULL) { char *p; if (buf[0] == '\n') continue; if ((p = strchr(buf, '\n')) != NULL) *p = '\0'; if (i >= 128) { fclose(f); fprintf(stderr, "ldrdf: too many input files\n"); exit(1); } *(respstrings + i) = nasm_strdup(buf); argc++, i++; } fclose(f); break; } case '2': options.stderr_redir = 1; error_file = stdout; break; case 'g': generic_rec_file = argv[1]; argv++, argc--; if (!argc) { fprintf(stderr, "ldrdf: -g expects a file name\n"); exit(1); } break; default: usage(); } argv++, argc--; } if (options.verbose > 4) { printf("ldrdf invoked with options:\n"); printf(" section alignment: %d bytes\n", options.align); printf(" output name: `%s'\n", outname); if (options.strip) printf(" strip symbols\n"); if (options.dynalink) printf(" Unix-style dynamic linking\n"); if (options.objpath) printf(" objects search path: %s\n", objpath); if (options.libpath) printf(" libraries search path: %s\n", libpath); printf("\n"); } symtab = symtabNew(); initsegments(); if (!symtab) { fprintf(stderr, "ldrdf: out of memory\n"); exit(1); } while (argc) { if (!*argv) argv = respstrings; if (!*argv) break; if (!strncmp(*argv, "-l", 2)) { if (libpath && (argv[0][2] != '/')) add_library(nasm_strcat(libpath, *argv + 2)); else add_library(*argv + 2); } else { if (objpath && (argv[0][0] != '/')) loadmodule(nasm_strcat(objpath, *argv)); else loadmodule(*argv); moduleloaded = 1; } argv++, argc--; } if (!moduleloaded) { printf("ldrdf: nothing to do. ldrdf -h for usage\n"); return 0; } search_libraries(); if (options.verbose > 2) { printf("symbol table:\n"); symtabDump(symtab, stdout); } write_output(outname); if (errorcount > 0) { remove(outname); exit(1); } return 0; }